Help on getting round stars with F5 GSO Newt

15.85 Dale Penkala #... · view views · 1 like
Jacob Heppell: Dale Penkala: I responded to this yesterday but for some reason it never went thru and didn’t get posted, but here is my take on your situation. 1st, You defiantly have collimation issues. Not only can you see it in the defocused image you can also see it in your focused image. This definitely needs to be addresses. 2nd, I also believe you have a pinched primary mirror. If you look at your defocused stars you can see they are slightly 3 lobbed which indicates a pinched primary mirror. 3rd, defiantly have coma and tilt. 4th, as @Jacob Heppell has pointed out a possible obstruction in the light path. So all of this will make a huge difference in your stars. The way I would approach this to correct it is as follows. 1) Remove the primary mirror cell and make an adjustment to the mirror clips. If you have any kind of adhesive tape holding the primary mirror to the cell I would absolutely remove it. This alone will give you issues! While you have the cell out I’d check to see how close your center spot is on the primary mirror and correct it if needed. 2) Once you get this done move to your initial collimation. When I have my ota’s off the mount working on them, I’ll do what I call bench collimation and make sure thats as good as I can get it. Tools range from a Cheshire to an auto collimator. Once thats done mount it and check collimation on the mount as it will change. Make the necessary adjustments. 3) Next get yourself a good coma corrector. My suggestion was posted above so I’ll stay with the Quattro because I use it and it’s done an excellent job for me. No matter what you did before this point if you don’t have a good CC you I will not see a whole lot of difference around the edges. Maybe the center part of the field. Back spacing will be important as well. My setup was 55mm and I added 1mm to compensate for a filter because I always shoot with one in place even if its a UV-IR Cut. 4) I would check to see about the obstruction in the light path. If there is something that can be done easily I’d suggest doing so. Ultimately as @Jacob Heppell said, you don’t want any obstruction in the light path if possible. Optional, If you really want to clean up your stars the next thing that I’d recommend is a mask to cover the mirror clips that hold the mirror in place. Its most noticeable in longer exposures but it will give you a much cleaner appearance for your stars. Hope this helps and good luck! Keep us informed on the progress! Dale Great explanation. This is more-or-less what I do when I'm helping local astro mates tune-in their newts. Problem is I'm not very good at explaining things on forums. So when mates in my region are explaining problems and need help I just tell them to come over to my place so I can actually eyeball what's going on as opposed to endlessly messaging back and forth. I also used to have minor problems with a pinched primary. A few years ago I siliconed my primary so I could get rid of the mirror clips but I soon noticed that the primary would pinch on cold nights (I probably didn't do the siliconing right anyway). When I found out about aperture masks, I un-siliconed the mirror and went with that option (see pictures) so now the primary sits freely in the cell and the aperture mask rests ~1-2mm above the mirror (supported by springs) to stop it falling out (also masks out any potential turned edge). Also, I found that the cork pads that support the primary occasionally would stick to the primary. Wiggling the primary would unstick it but it was nonetheless another source of pinching. Some flat nylon pads solved that issue. Newts (particularly fast newts) can be a challenge initially and the need for precision (collimation, centering mirrors/focuser, tilt, good CC, backspacing, focusing, etc) has been a turn-off for a number of people I know personally. But once you know your beast and get everything dialed in, the dividends a fast newt pays are more than worth it and will be a source of enjoyment for years (has been for me!). I agree totally! It’s a lot of work and tweaking things in but once it’s done it’s well worth it! Nice job on your mask! Dale Like

15.85

#...

· 1 like

Jacob Heppell:
Dale Penkala:
I responded to this yesterday but for some reason it never went thru and didn’t get posted, but here is my take on your situation.

1st, You defiantly have collimation issues. Not only can you see it in the defocused image you can also see it in your focused image. This definitely needs to be addresses.
2nd, I also believe you have a pinched primary mirror. If you look at your defocused stars you can see they are slightly 3 lobbed which indicates a pinched primary mirror.
3rd, defiantly have coma and tilt.
4th, as @Jacob Heppell has pointed out a possible obstruction in the light path.

So all of this will make a huge difference in your stars. The way I would approach this to correct it is as follows.

1) Remove the primary mirror cell and make an adjustment to the mirror clips. If you have any kind of adhesive tape holding the primary mirror to the cell I would absolutely remove it. This alone will give you issues! While you have the cell out I’d check to see how close your center spot is on the primary mirror and correct it if needed.
2) Once you get this done move to your initial collimation. When I have my ota’s off the mount working on them, I’ll do what I call bench collimation and make sure thats as good as I can get it. Tools range from a Cheshire to an auto collimator. Once thats done mount it and check collimation on the mount as it will change. Make the necessary adjustments.
3) Next get yourself a good coma corrector. My suggestion was posted above so I’ll stay with the Quattro because I use it and it’s done an excellent job for me. No matter what you did before this point if you don’t have a good CC you I will not see a whole lot of difference around the edges. Maybe the center part of the field. Back spacing will be important as well. My setup was 55mm and I added 1mm to compensate for a filter because I always shoot with one in place even if its a UV-IR Cut.
4) I would check to see about the obstruction in the light path. If there is something that can be done easily I’d suggest doing so. Ultimately as @Jacob Heppell said, you don’t want any obstruction in the light path if possible.

Optional, If you really want to clean up your stars the next thing that I’d recommend is a mask to cover the mirror clips that hold the mirror in place. Its most noticeable in longer exposures but it will give you a much cleaner appearance for your stars.

Hope this helps and good luck! Keep us informed on the progress!

Dale

Great explanation. This is more-or-less what I do when I'm helping local astro mates tune-in their newts. Problem is I'm not very good at explaining things on forums. So when mates in my region are explaining problems and need help I just tell them to come over to my place so I can actually eyeball what's going on as opposed to endlessly messaging back and forth.

I also used to have minor problems with a pinched primary. A few years ago I siliconed my primary so I could get rid of the mirror clips but I soon noticed that the primary would pinch on cold nights (I probably didn't do the siliconing right anyway). When I found out about aperture masks, I un-siliconed the mirror and went with that option (see pictures) so now the primary sits freely in the cell and the aperture mask rests ~1-2mm above the mirror (supported by springs) to stop it falling out (also masks out any potential turned edge). Also, I found that the cork pads that support the primary occasionally would stick to the primary. Wiggling the primary would unstick it but it was nonetheless another source of pinching. Some flat nylon pads solved that issue.

Newts (particularly fast newts) can be a challenge initially and the need for precision (collimation, centering mirrors/focuser, tilt, good CC, backspacing, focusing, etc) has been a turn-off for a number of people I know personally. But once you know your beast and get everything dialed in, the dividends a fast newt pays are more than worth it and will be a source of enjoyment for years (has been for me!).

I agree totally! It’s a lot of work and tweaking things in but once it’s done it’s well worth it! Nice job on your mask!

Dale

15.85 Dale Penkala #... · view views
Tareq Abdulla: Dale Penkala: Tareq Abdulla: Dale Penkala: Tom Marsala: Tareq Abdulla: the problem is with the secondary mirror Hey, Tareq. Sorry about that secondary! I know that mass produced secondaries are often a problem. I don't know how it affects star shapes, though. I just replaced my secondary from my 1980 Coulter 13" and it is tremendous, but costly (I could have bought three ZWO EAF's, haha!). It is an Ostahowski Optics handmade secondary and he takes his time making sure they are really flat. The coulter wasn't too bad, but undersized for photography. But it's taken me forty years to get to a point where I could buy it, haha! There are good secondaries out there: just make sure they are tested and whoever sold it to you will give you the numbers. Kind regards, Tom Slightly off topic but for anyone looking for high end secondary’s I highly recommend Antares Optical out of Rochester New York. I always used there secondaries in my Certified line of Newts. In all cases you get an interferometer sheet with the P-V rating. https://antaresoptics.com/ Dale I know this site, i was going to order from them when i was planning to build a 20" dobsonian [and still in this plan hopefully soon in future], but i can't tell about this minor axis size i should choose and which P-V rating, i mean is it really necessary to go all the way to the maximum 1/30 PV one. Hello Tareq, When I built my certified newts this always the company I bought my mirrors from. It really comes down to what you have to spend honestly, but first it’s been my experience that even the lowest P-V rating is significantly better than any stock mass manufactured scopes secondaries. I always put in the lowest wavefront secondary unless the customer wanted a better one. In most cases people would upgrade to the 1/16 - 1/20th wave. In my case for visual I went with 1/30th quartz but that was just me and my personal scope. When I upgraded my 12” I went with 1/15th for a couple of reasons, 1st cost obviously, second and probably more common sense related here in Michigan our seeing very rarely gets to 2” of seeing so really unless you have excellent seeing conditions your wasting your money at least in my eyes anyway so thats why I did what I did. Bottom line is if you bought their lowest wavefront secondary to replace a stock GSO, Syntha, etc… you will certainly have a much better secondary mirror. I just can’t recommend them enough. Thats why I wanted to post this for others. Not many know that they do secondary mirrors for the astronomical community. If memory serves me correctly they do a lot of government work. As for your 20” dob, what is the Strehl Ratio of your primary? If you really want to pull the best images from a primary with a high strehl then I’d move for something closer to the 1/18th wave but remember seeing will most likely be your limiting factor. Dale Hello Dale, This is a big topic really, i watched this site for a while and i know they are making high end secondary mirrors and even lowest one is better than all mass production ones we are using no doubt, but i didn't upgrade as i had another issues with my Newt, once i fix those which i did to some points then i can think about upgrading the secondary or even primary mirrors, but those are for imaging so primary is doing fine for now. Regarding 20" dob, i still don't know anything, because i am not sure i will build or i buy one ready cheapest i can find around, i once talked with one guy who told me that he can build a structure only for me for that 20" design at very very low cost but good materials and quality, i am not after high end materials and design to pay fortune even for structure alone, and for mirrors i was planning to go with Antares optics secondary mirror and something like Zambuto Quartz primary mirror although bloody expensive, but at least i got something or started, now i feel like i will just buy any 20" dob i can find the cheapest even as mass production and then i replace parts including mirrors by myself later, pity that Europe and USA dobs designs are very expensive, the guy that talked with me about the design is Asian, so i assume i have to look at Asia craftsmanship who can design one for me at cheapest it can be with enough proper quality at least, i wish to make a Newt 20" so i can use it with EQ mount rather than AZ/Alt or EQ platform, but well, i also think about visual, that dob is actually mainly for planetary imaging, i don't want to use 11"-16" SCT for that at all, and 20" is another class for both visual and imaging anyway. About seeing condition, build me one 20" and then i will show you what is a nice excellent seeing condition means from here Tareq You are correct Tareq, it is a big topic and honestly for this thread is off topic, but I thought I’d just get that in for others that may have that question. Dale Like

15.85

Dale Penkala

#...

Tareq Abdulla:
Dale Penkala:
Tareq Abdulla:
Dale Penkala:
Tom Marsala:
Tareq Abdulla:
the problem is with the secondary mirror

Hey, Tareq. Sorry about that secondary! I know that mass produced secondaries are often a problem. I don't know how it affects star shapes, though. I just replaced my secondary from my 1980 Coulter 13" and it is tremendous, but costly (I could have bought three ZWO EAF's, haha!). It is an Ostahowski Optics handmade secondary and he takes his time making sure they are really flat. The coulter wasn't too bad, but undersized for photography. But it's taken me forty years to get to a point where I could buy it, haha! There are good secondaries out there: just make sure they are tested and whoever sold it to you will give you the numbers.

Kind regards,
Tom

Slightly off topic but for anyone looking for high end secondary’s I highly recommend Antares Optical out of Rochester New York. I always used there secondaries in my Certified line of Newts. In all cases you get an interferometer sheet with the P-V rating.

https://antaresoptics.com/

Dale

I know this site, i was going to order from them when i was planning to build a 20" dobsonian [and still in this plan hopefully soon in future], but i can't tell about this minor axis size i should choose and which P-V rating, i mean is it really necessary to go all the way to the maximum 1/30 PV one.

Hello Tareq,
When I built my certified newts this always the company I bought my mirrors from.
It really comes down to what you have to spend honestly, but first it’s been my experience that even the lowest P-V rating is significantly better than any stock mass manufactured scopes secondaries. I always put in the lowest wavefront secondary unless the customer wanted a better one. In most cases people would upgrade to the 1/16 - 1/20th wave. In my case for visual I went with 1/30th quartz but that was just me and my personal scope. When I upgraded my 12” I went with 1/15th for a couple of reasons, 1st cost obviously, second and probably more common sense related here in Michigan our seeing very rarely gets to 2” of seeing so really unless you have excellent seeing conditions your wasting your money at least in my eyes anyway so thats why I did what I did. Bottom line is if you bought their lowest wavefront secondary to replace a stock GSO, Syntha, etc… you will certainly have a much better secondary mirror. I just can’t recommend them enough. Thats why I wanted to post this for others. Not many know that they do secondary mirrors for the astronomical community. If memory serves me correctly they do a lot of government work.

As for your 20” dob, what is the Strehl Ratio of your primary? If you really want to pull the best images from a primary with a high strehl then I’d move for something closer to the 1/18th wave but remember seeing will most likely be your limiting factor.

Dale

Hello Dale,

This is a big topic really, i watched this site for a while and i know they are making high end secondary mirrors and even lowest one is better than all mass production ones we are using no doubt, but i didn't upgrade as i had another issues with my Newt, once i fix those which i did to some points then i can think about upgrading the secondary or even primary mirrors, but those are for imaging so primary is doing fine for now.

Regarding 20" dob, i still don't know anything, because i am not sure i will build or i buy one ready cheapest i can find around, i once talked with one guy who told me that he can build a structure only for me for that 20" design at very very low cost but good materials and quality, i am not after high end materials and design to pay fortune even for structure alone, and for mirrors i was planning to go with Antares optics secondary mirror and something like Zambuto Quartz primary mirror although bloody expensive, but at least i got something or started, now i feel like i will just buy any 20" dob i can find the cheapest even as mass production and then i replace parts including mirrors by myself later, pity that Europe and USA dobs designs are very expensive, the guy that talked with me about the design is Asian, so i assume i have to look at Asia craftsmanship who can design one for me at cheapest it can be with enough proper quality at least, i wish to make a Newt 20" so i can use it with EQ mount rather than AZ/Alt or EQ platform, but well, i also think about visual, that dob is actually mainly for planetary imaging, i don't want to use 11"-16" SCT for that at all, and 20" is another class for both visual and imaging anyway.

About seeing condition, build me one 20" and then i will show you what is a nice excellent seeing condition means from here

Tareq

You are correct Tareq, it is a big topic and honestly for this thread is off topic, but I thought I’d just get that in for others that may have that question.

Dale

15.85 Dale Penkala #... · view views · 1 like
Yes I replaced my stock secondary with one from Antares Optics. Optically it was great but was way too thick, which meant I couldn't raise it high enough to be properly centered with the focuser (thickness wasn't stated on the website at the time so had no idea!). I've since replaced it with an Orion Optics mirror, which are optically great and a reasonable thickness. Yes they are a thicker mirror and I personally like that but in my case when I upgraded my Certified Newts I machined custom secondary holders which allowed me to compensate for that extra thickness. Bottom line is they make excellent secondary mirrors, but you just need to make sure it all works out in the end. I still highly recommend there secondary mirrors. Dale Edited ... Like

15.85

Dale Penkala

#...

· 1 like

Yes I replaced my stock secondary with one from Antares Optics. Optically it was great but was way too thick, which meant I couldn't raise it high enough to be properly centered with the focuser (thickness wasn't stated on the website at the time so had no idea!). I've since replaced it with an Orion Optics mirror, which are optically great and a reasonable thickness.

Yes they are a thicker mirror and I personally like that but in my case when I upgraded my Certified Newts I machined custom secondary holders which allowed me to compensate for that extra thickness. Bottom line is they make excellent secondary mirrors, but you just need to make sure it all works out in the end. I still highly recommend there secondary mirrors.

Dale

Edited ...

1.20 Jacob Heppell #... · view views · 1 like
Dale Penkala: Yes they are a thicker mirror and I personally like that but in my case when I upgraded my Certified Newts I machined custom secondary holders which allowed me to compensate for that extra thickness. Bottom line is they make excellent secondary mirrors, but you just need to make sure it all works out in the end. I still highly recommend there secondary mirrors. Dale I also considered getting a shorter holder, which may have helped somewhat but the other problem was that the the top of the Antares secondary was only a few mm from touching the spider. I estimated I needed at least an extra 5mm to get proper centering while also clearing the spider. It's nothing against Antares as the mirror was great and the extra thickness is appealing. The problem was that my 10" quattro simply couldn't accommodate the mirror so I was forced to source a thinner secondary. The main reason I wanted to upgrade the secondary was that the stock mirror was only 82mm and won't fully illuminate an APS-C sensor whereas a 90mm will. I understand the latest 10" quattros come with 90mm secondary's. Like

1.20

Jacob Heppell

#...

· 1 like

Dale Penkala:
Yes they are a thicker mirror and I personally like that but in my case when I upgraded my Certified Newts I machined custom secondary holders which allowed me to compensate for that extra thickness. Bottom line is they make excellent secondary mirrors, but you just need to make sure it all works out in the end. I still highly recommend there secondary mirrors.

Dale

I also considered getting a shorter holder, which may have helped somewhat but the other problem was that the the top of the Antares secondary was only a few mm from touching the spider. I estimated I needed at least an extra 5mm to get proper centering while also clearing the spider. It's nothing against Antares as the mirror was great and the extra thickness is appealing. The problem was that my 10" quattro simply couldn't accommodate the mirror so I was forced to source a thinner secondary.
The main reason I wanted to upgrade the secondary was that the stock mirror was only 82mm and won't fully illuminate an APS-C sensor whereas a 90mm will. I understand the latest 10" quattros come with 90mm secondary's.

15.85 Dale Penkala #... · view views · 1 like
Jacob Heppell: Dale Penkala: Yes they are a thicker mirror and I personally like that but in my case when I upgraded my Certified Newts I machined custom secondary holders which allowed me to compensate for that extra thickness. Bottom line is they make excellent secondary mirrors, but you just need to make sure it all works out in the end. I still highly recommend there secondary mirrors. Dale I also considered getting a shorter holder, which may have helped somewhat but the other problem was that the the top of the Antares secondary was only a few mm from touching the spider. I estimated I needed at least an extra 5mm to get proper centering while also clearing the spider. It's nothing against Antares as the mirror was great and the extra thickness is appealing. The problem was that my 10" quattro simply couldn't accommodate the mirror so I was forced to source a thinner secondary. The main reason I wanted to upgrade the secondary was that the stock mirror was only 82mm and won't fully illuminate an APS-C sensor whereas a 90mm will. I understand the latest 10" quattros come with 90mm secondary's. Absolutely, you have to do what works for your setup so you did what you had to do. Glad you were successful with your upgrade! Dale Like

15.85

Dale Penkala

#...

· 1 like

Jacob Heppell:
Dale Penkala:
Yes they are a thicker mirror and I personally like that but in my case when I upgraded my Certified Newts I machined custom secondary holders which allowed me to compensate for that extra thickness. Bottom line is they make excellent secondary mirrors, but you just need to make sure it all works out in the end. I still highly recommend there secondary mirrors.

Dale

I also considered getting a shorter holder, which may have helped somewhat but the other problem was that the the top of the Antares secondary was only a few mm from touching the spider. I estimated I needed at least an extra 5mm to get proper centering while also clearing the spider. It's nothing against Antares as the mirror was great and the extra thickness is appealing. The problem was that my 10" quattro simply couldn't accommodate the mirror so I was forced to source a thinner secondary.
The main reason I wanted to upgrade the secondary was that the stock mirror was only 82mm and won't fully illuminate an APS-C sensor whereas a 90mm will. I understand the latest 10" quattros come with 90mm secondary's.

Absolutely, you have to do what works for your setup so you did what you had to do. Glad you were successful with your upgrade!

Dale

2.94 Tareq Abdulla #... · view views
And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem. For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP. Like

2.94

Tareq Abdulla

#...

And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem.

For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP.

1.20 Jacob Heppell #... · view views · 1 like
Tareq Abdulla: And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem. Collimation screws in general are bad for torquing the central stub causing the mirror to twist. My work around for that problem was to place a washer between the stub and collimation screws with holes drilled in the washer where the collimation screws sit. Tareq Abdulla: For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP. Clean mirrors as infrequently as you can. Don't inspect the mirror using a torch light as every bit of microscopic dust will show up brightly. Just look at it under normal lighting. If it's clearly getting a bit filthy then time for a clean. There's a few ways folks clean their mirrors but tap water and detergent are pretty common using the gentle stroke of cotton buds or finger tips. Once clean, a rinse off with distilled water then stand to dry. Gently dab any bits of water off with a tissue or something. As for collimation, the gold standard is a catseye cheshire and autocollimator. That's what I use. Edited ... Like

1.20

Jacob Heppell

#...

· 1 like

Tareq Abdulla:
And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem.

Collimation screws in general are bad for torquing the central stub causing the mirror to twist. My work around for that problem was to place a washer between the stub and collimation screws with holes drilled in the washer where the collimation screws sit.

Tareq Abdulla:
For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP.

Clean mirrors as infrequently as you can. Don't inspect the mirror using a torch light as every bit of microscopic dust will show up brightly. Just look at it under normal lighting. If it's clearly getting a bit filthy then time for a clean. There's a few ways folks clean their mirrors but tap water and detergent are pretty common using the gentle stroke of cotton buds or finger tips. Once clean, a rinse off with distilled water then stand to dry. Gently dab any bits of water off with a tissue or something.
As for collimation, the gold standard is a catseye cheshire and autocollimator. That's what I use.

Edited ...

2.94 Tareq Abdulla #... · view views
Jacob Heppell: Tareq Abdulla: And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem. Collimation screws in general are bad for torquing the central stub causing the mirror to twist. My work around for that problem was to place a washer between the stub and collimation screws with holes drilled in the washer where the collimation screws sit. Tareq Abdulla: For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP. Clean mirrors as infrequently as you can. Don't inspect the mirror using a torch light as every bit of microscopic dust will show up brightly. Just look at it under normal lighting. If it's clearly getting a bit filthy then time for a clean. There's a few ways folks clean their mirrors but tap water and detergent are pretty common using the gentle stroke of cotton buds or finger tips. Once clean, a rinse off with distilled water then stand to dry. Gently dab any bits of water off with a tissue or something. As for collimation, the gold standard is a catseye cheshire and autocollimator. That's what I use. A. I replaced those screws to Bob's knobs which all are swearing about it, i did for both Newts, but it worked with my 8" and not with 6", there is another issue i can't figure out, the collimation with 8" is like straight forward and all knobs working independently, while with 6", only two knobs from any direction is working, once i touch the third it is kind of reset and ruin the collimation, i have to use all knobs, no point only two are accessible. B. I will try to clean and rinse gently, i thought we can't clean those mirrors by water and any kind of detergent, also didn't know we can wipe it with cotton or cloth sort of, i thought all those will damage any protection has been applied to the mirror or it might scratch it, definitely i am not trying to remove every single atomic dust there but at least those dust and hair that can be seen even without any light. C. I thought the best top end only collimator is Howie Glatter, and then Catseye, i am not sure which one will choose, i have Cheshire that i use with my 8" very simple and even with my 6" just ok, primary mirror isn't my main problem actually, it was only the secondary, so i will see how i can get that fixed before i buy extra but better collimator. Like

2.94

Tareq Abdulla

#...

Jacob Heppell:
Tareq Abdulla:
And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem.

Collimation screws in general are bad for torquing the central stub causing the mirror to twist. My work around for that problem was to place a washer between the stub and collimation screws with holes drilled in the washer where the collimation screws sit.
Tareq Abdulla:
For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP.

Clean mirrors as infrequently as you can. Don't inspect the mirror using a torch light as every bit of microscopic dust will show up brightly. Just look at it under normal lighting. If it's clearly getting a bit filthy then time for a clean. There's a few ways folks clean their mirrors but tap water and detergent are pretty common using the gentle stroke of cotton buds or finger tips. Once clean, a rinse off with distilled water then stand to dry. Gently dab any bits of water off with a tissue or something.
As for collimation, the gold standard is a catseye cheshire and autocollimator. That's what I use.

A. I replaced those screws to Bob's knobs which all are swearing about it, i did for both Newts, but it worked with my 8" and not with 6", there is another issue i can't figure out, the collimation with 8" is like straight forward and all knobs working independently, while with 6", only two knobs from any direction is working, once i touch the third it is kind of reset and ruin the collimation, i have to use all knobs, no point only two are accessible.

B. I will try to clean and rinse gently, i thought we can't clean those mirrors by water and any kind of detergent, also didn't know we can wipe it with cotton or cloth sort of, i thought all those will damage any protection has been applied to the mirror or it might scratch it, definitely i am not trying to remove every single atomic dust there but at least those dust and hair that can be seen even without any light.

C. I thought the best top end only collimator is Howie Glatter, and then Catseye, i am not sure which one will choose, i have Cheshire that i use with my 8" very simple and even with my 6" just ok, primary mirror isn't my main problem actually, it was only the secondary, so i will see how i can get that fixed before i buy extra but better collimator.

15.85 Dale Penkala #... · view views
Tareq Abdulla: And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem. For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP. Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine. Dale Like

15.85

Dale Penkala

#...

Tareq Abdulla:
And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem.

For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP.

Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine.

Dale

15.85 Dale Penkala #... · view views · 1 like
I thought I’d post this for people that are following this thread. While collimation really wasn’t the topic of the original poster, it is a major part to getting round stars. We all have our own way on how we do things but there is a general workflow on collimation. I found this article sometime ago and I liked some of the explanation's in it so I kept it. Photonewton_Collimation_Primer.pdf Hope this helps some of you. Dale Like

15.85

Dale Penkala

#...

· 1 like

I thought I’d post this for people that are following this thread. While collimation really wasn’t the topic of the original poster, it is a major part to getting round stars. We all have our own way on how we do things but there is a general workflow on collimation. I found this article sometime ago and I liked some of the explanation's in it so I kept it.

Photonewton_Collimation_Primer.pdf

Hope this helps some of you.

Dale

2.94 Tareq Abdulla #... · view views
Dale Penkala: Tareq Abdulla: And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem. For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP. Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine. Dale I won't give up the scope, doesn't matter if the design is bad, in fact my 8" F/5 is just from Meade a discontinued one and i got it as the last piece brand new cheaper than that 6" f/4 actually which is surprising, but if this issue is available to all or most of that GSO 6" F/4 then i have to solution but to force the collimation manually by hand somehow and glue it by tapes, i have no plan to sell this 6" or buy another one as a high end or better design. Like

2.94

Tareq Abdulla

#...

Dale Penkala:
Tareq Abdulla:
And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem.

For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP.

Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine.

Dale

I won't give up the scope, doesn't matter if the design is bad, in fact my 8" F/5 is just from Meade a discontinued one and i got it as the last piece brand new cheaper than that 6" f/4 actually which is surprising, but if this issue is available to all or most of that GSO 6" F/4 then i have to solution but to force the collimation manually by hand somehow and glue it by tapes, i have no plan to sell this 6" or buy another one as a high end or better design.

15.85 Dale Penkala #... · view views
Tareq Abdulla: Dale Penkala: Tareq Abdulla: And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem. For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP. Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine. Dale I won't give up the scope, doesn't matter if the design is bad, in fact my 8" F/5 is just from Meade a discontinued one and i got it as the last piece brand new cheaper than that 6" f/4 actually which is surprising, but if this issue is available to all or most of that GSO 6" F/4 then i have to solution but to force the collimation manually by hand somehow and glue it by tapes, i have no plan to sell this 6" or buy another one as a high end or better design. I didn’t give up on it but it’s not mine and I’d rip it apart and start from scratch if it was mine. I have my 10” and 12” f5 newts that work quite well and my new Stellarvue SVX102 for the wider field images so no need to even mess with it, and he upgraded to an 8” f5 and is very happy with the performance of it. Dale Edited ... Like

15.85

Dale Penkala

#...

Tareq Abdulla:
Dale Penkala:
Tareq Abdulla:
And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem.

For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP.

Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine.

Dale

I won't give up the scope, doesn't matter if the design is bad, in fact my 8" F/5 is just from Meade a discontinued one and i got it as the last piece brand new cheaper than that 6" f/4 actually which is surprising, but if this issue is available to all or most of that GSO 6" F/4 then i have to solution but to force the collimation manually by hand somehow and glue it by tapes, i have no plan to sell this 6" or buy another one as a high end or better design.

I didn’t give up on it but it’s not mine and I’d rip it apart and start from scratch if it was mine. I have my 10” and 12” f5 newts that work quite well and my new Stellarvue SVX102 for the wider field images so no need to even mess with it, and he upgraded to an 8” f5 and is very happy with the performance of it.

Dale

Edited ...

9.53 Elmiko #... · view views
I would suggest that you get a laser collimator. I have the Orion one works well. the artifact (shadow) is the focus tube protruding into the light path of the Telescope. I I've heard of people cutting it shorter. Mike Like

2.94 Tareq Abdulla #... · view views
Dale Penkala: Tareq Abdulla: Dale Penkala: Tareq Abdulla: And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem. For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP. Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine. Dale I won't give up the scope, doesn't matter if the design is bad, in fact my 8" F/5 is just from Meade a discontinued one and i got it as the last piece brand new cheaper than that 6" f/4 actually which is surprising, but if this issue is available to all or most of that GSO 6" F/4 then i have to solution but to force the collimation manually by hand somehow and glue it by tapes, i have no plan to sell this 6" or buy another one as a high end or better design. I didn’t give up on it but it’s not mine and I’d rip it apart and start from scratch if it was mine. I have my 10” and 12” f5 newts that work quite well and my new Stellarvue SVX102 for the wider field images so no need to even mess with it, and he upgraded to an 8” f5 and is very happy with the performance of it. Dale If i remember correctly i think i ordered that GSO 6" F/4 by 2021, and i didn't try to play with it from scratch yet, and with few times i tested collimation i really failed, even it became worse last year when i tried to image a planet [Jupiter] which i immediately changed to my Mak and i got an amazing successful result and then i never touched that 6" again, so i am not sure when and how to do so, and my mistake is that i didn't play with my 8" F/5 enough really which will make really amazing results i am sure, hopefully this year. Like

2.94

Tareq Abdulla

#...

Dale Penkala:
Tareq Abdulla:
Dale Penkala:
Tareq Abdulla:
And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem.

For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP.

Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine.

Dale

I won't give up the scope, doesn't matter if the design is bad, in fact my 8" F/5 is just from Meade a discontinued one and i got it as the last piece brand new cheaper than that 6" f/4 actually which is surprising, but if this issue is available to all or most of that GSO 6" F/4 then i have to solution but to force the collimation manually by hand somehow and glue it by tapes, i have no plan to sell this 6" or buy another one as a high end or better design.

I didn’t give up on it but it’s not mine and I’d rip it apart and start from scratch if it was mine. I have my 10” and 12” f5 newts that work quite well and my new Stellarvue SVX102 for the wider field images so no need to even mess with it, and he upgraded to an 8” f5 and is very happy with the performance of it.

Dale

If i remember correctly i think i ordered that GSO 6" F/4 by 2021, and i didn't try to play with it from scratch yet, and with few times i tested collimation i really failed, even it became worse last year when i tried to image a planet [Jupiter] which i immediately changed to my Mak and i got an amazing successful result and then i never touched that 6" again, so i am not sure when and how to do so, and my mistake is that i didn't play with my 8" F/5 enough really which will make really amazing results i am sure, hopefully this year.

1.20 Jacob Heppell #... · view views
Tareq Abdulla: C. I thought the best top end only collimator is Howie Glatter, and then Catseye, i am not sure which one will choose, i have Cheshire that i use with my 8" very simple and even with my 6" just ok, primary mirror isn't my main problem actually, it was only the secondary, so i will see how i can get that fixed before i buy extra but better collimator. Laser collimators don't have the sensitivity of the catseye system so I don't recommend them for a telescope used for astrophotography. Plus the lasers themselves are often not well collimated (I know this from personal experience with laser collimators). Although, for a slow (~F5 or slower) visual scope, you could probably get away with using a good quality laser (perhaps the Howie Glatter you mentioned) more-so if it's a barlowed laser. Tareq Abdulla: B. I will try to clean and rinse gently, i thought we can't clean those mirrors by water and any kind of detergent, also didn't know we can wipe it with cotton or cloth sort of, i thought all those will damage any protection has been applied to the mirror or it might scratch it, definitely i am not trying to remove every single atomic dust there but at least those dust and hair that can be seen even without any light. The mirror coatings can be scratched but they are not as delicate as you think. Any loose dust and grit should be rinsed off first before cleaning as I can imagine that a speck of sand if dragged across the mirror may create a scratch. I've cleaned my mirror using water/detergent and my finger tips a few times without issue. It takes a lot of dust and grim on the primary before there is any sort of measurable reduction in image contrast. Even if you accidentally put a slight scratch in the mirror, you won't see it in your images. Tareq Abdulla: A. I replaced those screws to Bob's knobs which all are swearing about it, i did for both Newts, but it worked with my 8" and not with 6", there is another issue i can't figure out, the collimation with 8" is like straight forward and all knobs working independently, while with 6", only two knobs from any direction is working, once i touch the third it is kind of reset and ruin the collimation, i have to use all knobs, no point only two are accessible. The "third knob" you mention is probably grabbing onto the secondary stub and twisting it, which will cause the problem you mentioned. Also, you only need to adjust two out of three knobs (primary and secondary) to collimate the mirrors. For me, this is preferable because if you adjust all three you might find that the vertical position of your mirrors changes over time if you're loosening/tightening all three knobs. Like

1.20

Jacob Heppell

#...

Tareq Abdulla:
C. I thought the best top end only collimator is Howie Glatter, and then Catseye, i am not sure which one will choose, i have Cheshire that i use with my 8" very simple and even with my 6" just ok, primary mirror isn't my main problem actually, it was only the secondary, so i will see how i can get that fixed before i buy extra but better collimator.

Laser collimators don't have the sensitivity of the catseye system so I don't recommend them for a telescope used for astrophotography. Plus the lasers themselves are often not well collimated (I know this from personal experience with laser collimators). Although, for a slow (~F5 or slower) visual scope, you could probably get away with using a good quality laser (perhaps the Howie Glatter you mentioned) more-so if it's a barlowed laser.

Tareq Abdulla:
B. I will try to clean and rinse gently, i thought we can't clean those mirrors by water and any kind of detergent, also didn't know we can wipe it with cotton or cloth sort of, i thought all those will damage any protection has been applied to the mirror or it might scratch it, definitely i am not trying to remove every single atomic dust there but at least those dust and hair that can be seen even without any light.

The mirror coatings can be scratched but they are not as delicate as you think. Any loose dust and grit should be rinsed off first before cleaning as I can imagine that a speck of sand if dragged across the mirror may create a scratch. I've cleaned my mirror using water/detergent and my finger tips a few times without issue.
It takes a lot of dust and grim on the primary before there is any sort of measurable reduction in image contrast. Even if you accidentally put a slight scratch in the mirror, you won't see it in your images.

Tareq Abdulla:
A. I replaced those screws to Bob's knobs which all are swearing about it, i did for both Newts, but it worked with my 8" and not with 6", there is another issue i can't figure out, the collimation with 8" is like straight forward and all knobs working independently, while with 6", only two knobs from any direction is working, once i touch the third it is kind of reset and ruin the collimation, i have to use all knobs, no point only two are accessible.

The "third knob" you mention is probably grabbing onto the secondary stub and twisting it, which will cause the problem you mentioned. Also, you only need to adjust two out of three knobs (primary and secondary) to collimate the mirrors. For me, this is preferable because if you adjust all three you might find that the vertical position of your mirrors changes over time if you're loosening/tightening all three knobs.

15.85 Dale Penkala #... · view views · 1 like
Tareq Abdulla: Dale Penkala: Tareq Abdulla: Dale Penkala: Tareq Abdulla: And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem. For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP. Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine. Dale I won't give up the scope, doesn't matter if the design is bad, in fact my 8" F/5 is just from Meade a discontinued one and i got it as the last piece brand new cheaper than that 6" f/4 actually which is surprising, but if this issue is available to all or most of that GSO 6" F/4 then i have to solution but to force the collimation manually by hand somehow and glue it by tapes, i have no plan to sell this 6" or buy another one as a high end or better design. I didn’t give up on it but it’s not mine and I’d rip it apart and start from scratch if it was mine. I have my 10” and 12” f5 newts that work quite well and my new Stellarvue SVX102 for the wider field images so no need to even mess with it, and he upgraded to an 8” f5 and is very happy with the performance of it. Dale If i remember correctly i think i ordered that GSO 6" F/4 by 2021, and i didn't try to play with it from scratch yet, and with few times i tested collimation i really failed, even it became worse last year when i tried to image a planet [Jupiter] which i immediately changed to my Mak and i got an amazing successful result and then i never touched that 6" again, so i am not sure when and how to do so, and my mistake is that i didn't play with my 8" F/5 enough really which will make really amazing results i am sure, hopefully this year. Yup I get it! Its hard to go back to something you struggle with when you have good success with something else! Dale Like

15.85

Dale Penkala

#...

· 1 like

Tareq Abdulla:
Dale Penkala:
Tareq Abdulla:
Dale Penkala:
Tareq Abdulla:
And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem.

For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP.

Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine.

Dale

I won't give up the scope, doesn't matter if the design is bad, in fact my 8" F/5 is just from Meade a discontinued one and i got it as the last piece brand new cheaper than that 6" f/4 actually which is surprising, but if this issue is available to all or most of that GSO 6" F/4 then i have to solution but to force the collimation manually by hand somehow and glue it by tapes, i have no plan to sell this 6" or buy another one as a high end or better design.

I didn’t give up on it but it’s not mine and I’d rip it apart and start from scratch if it was mine. I have my 10” and 12” f5 newts that work quite well and my new Stellarvue SVX102 for the wider field images so no need to even mess with it, and he upgraded to an 8” f5 and is very happy with the performance of it.

Dale

If i remember correctly i think i ordered that GSO 6" F/4 by 2021, and i didn't try to play with it from scratch yet, and with few times i tested collimation i really failed, even it became worse last year when i tried to image a planet [Jupiter] which i immediately changed to my Mak and i got an amazing successful result and then i never touched that 6" again, so i am not sure when and how to do so, and my mistake is that i didn't play with my 8" F/5 enough really which will make really amazing results i am sure, hopefully this year.

Yup I get it! Its hard to go back to something you struggle with when you have good success with something else!

Dale

2.94 Tareq Abdulla #... · view views
Dale Penkala: Tareq Abdulla: Dale Penkala: Tareq Abdulla: Dale Penkala: Tareq Abdulla: And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem. For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP. Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine. Dale I won't give up the scope, doesn't matter if the design is bad, in fact my 8" F/5 is just from Meade a discontinued one and i got it as the last piece brand new cheaper than that 6" f/4 actually which is surprising, but if this issue is available to all or most of that GSO 6" F/4 then i have to solution but to force the collimation manually by hand somehow and glue it by tapes, i have no plan to sell this 6" or buy another one as a high end or better design. I didn’t give up on it but it’s not mine and I’d rip it apart and start from scratch if it was mine. I have my 10” and 12” f5 newts that work quite well and my new Stellarvue SVX102 for the wider field images so no need to even mess with it, and he upgraded to an 8” f5 and is very happy with the performance of it. Dale If i remember correctly i think i ordered that GSO 6" F/4 by 2021, and i didn't try to play with it from scratch yet, and with few times i tested collimation i really failed, even it became worse last year when i tried to image a planet [Jupiter] which i immediately changed to my Mak and i got an amazing successful result and then i never touched that 6" again, so i am not sure when and how to do so, and my mistake is that i didn't play with my 8" F/5 enough really which will make really amazing results i am sure, hopefully this year. Yup I get it! Its hard to go back to something you struggle with when you have good success with something else! Dale The point was that since i bought my second Newt of 6" F/4 then i started to buy more and more of refractors, which forced me to think about smaller scopes and few accessories and i forgot about the big scopes, and last year i also bought 10" RC but i never took it out of the box as i can't use it yet, now i am not sure if i use that RC will i go back to Newt at all, and i don't want to have headache as well with RC, good i bought that Truss design which has like the primary mirror independent from the focuser which is making collimation easier, but not sure how and which collimator really, and many i saw just changed the stock focuser, which means the collimation will be affected for sure if i change, but i won't use it until i am ready [my mount can't handle it yet without enough counterweights]. Back for this main topic, i remember once when i tried my 6" F/4 with almost as much collimation close i can get the stars still weren't round by edges, i don't know if that was the collimation or the back focus or unbalancing and guiding issue or all of them, i hate to deal with so many issues at once and still can't fix it completely perfectly, in 2021 was very bad year for me, and last year 2022 i was busy only to buy stuff before all prices and items gone or changed, now this year i can return back to imaging with all what i have, just need to make sure i have all tools i need rather than go out many nights and only dealing with issues more than imaging itself, wasted few years already so enough. Like

2.94

Tareq Abdulla

#...

Dale Penkala:
Tareq Abdulla:
Dale Penkala:
Tareq Abdulla:
Dale Penkala:
Tareq Abdulla:
And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem.

For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP.

Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine.

Dale

I won't give up the scope, doesn't matter if the design is bad, in fact my 8" F/5 is just from Meade a discontinued one and i got it as the last piece brand new cheaper than that 6" f/4 actually which is surprising, but if this issue is available to all or most of that GSO 6" F/4 then i have to solution but to force the collimation manually by hand somehow and glue it by tapes, i have no plan to sell this 6" or buy another one as a high end or better design.

I didn’t give up on it but it’s not mine and I’d rip it apart and start from scratch if it was mine. I have my 10” and 12” f5 newts that work quite well and my new Stellarvue SVX102 for the wider field images so no need to even mess with it, and he upgraded to an 8” f5 and is very happy with the performance of it.

Dale

If i remember correctly i think i ordered that GSO 6" F/4 by 2021, and i didn't try to play with it from scratch yet, and with few times i tested collimation i really failed, even it became worse last year when i tried to image a planet [Jupiter] which i immediately changed to my Mak and i got an amazing successful result and then i never touched that 6" again, so i am not sure when and how to do so, and my mistake is that i didn't play with my 8" F/5 enough really which will make really amazing results i am sure, hopefully this year.

Yup I get it! Its hard to go back to something you struggle with when you have good success with something else!

Dale

The point was that since i bought my second Newt of 6" F/4 then i started to buy more and more of refractors, which forced me to think about smaller scopes and few accessories and i forgot about the big scopes, and last year i also bought 10" RC but i never took it out of the box as i can't use it yet, now i am not sure if i use that RC will i go back to Newt at all, and i don't want to have headache as well with RC, good i bought that Truss design which has like the primary mirror independent from the focuser which is making collimation easier, but not sure how and which collimator really, and many i saw just changed the stock focuser, which means the collimation will be affected for sure if i change, but i won't use it until i am ready [my mount can't handle it yet without enough counterweights].

Back for this main topic, i remember once when i tried my 6" F/4 with almost as much collimation close i can get the stars still weren't round by edges, i don't know if that was the collimation or the back focus or unbalancing and guiding issue or all of them, i hate to deal with so many issues at once and still can't fix it completely perfectly, in 2021 was very bad year for me, and last year 2022 i was busy only to buy stuff before all prices and items gone or changed, now this year i can return back to imaging with all what i have, just need to make sure i have all tools i need rather than go out many nights and only dealing with issues more than imaging itself, wasted few years already so enough.

15.85 Dale Penkala #... · view views
Tareq Abdulla: Dale Penkala: Tareq Abdulla: Dale Penkala: Tareq Abdulla: Dale Penkala: Tareq Abdulla: And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem. For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP. Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine. Dale I won't give up the scope, doesn't matter if the design is bad, in fact my 8" F/5 is just from Meade a discontinued one and i got it as the last piece brand new cheaper than that 6" f/4 actually which is surprising, but if this issue is available to all or most of that GSO 6" F/4 then i have to solution but to force the collimation manually by hand somehow and glue it by tapes, i have no plan to sell this 6" or buy another one as a high end or better design. I didn’t give up on it but it’s not mine and I’d rip it apart and start from scratch if it was mine. I have my 10” and 12” f5 newts that work quite well and my new Stellarvue SVX102 for the wider field images so no need to even mess with it, and he upgraded to an 8” f5 and is very happy with the performance of it. Dale If i remember correctly i think i ordered that GSO 6" F/4 by 2021, and i didn't try to play with it from scratch yet, and with few times i tested collimation i really failed, even it became worse last year when i tried to image a planet [Jupiter] which i immediately changed to my Mak and i got an amazing successful result and then i never touched that 6" again, so i am not sure when and how to do so, and my mistake is that i didn't play with my 8" F/5 enough really which will make really amazing results i am sure, hopefully this year. Yup I get it! Its hard to go back to something you struggle with when you have good success with something else! Dale The point was that since i bought my second Newt of 6" F/4 then i started to buy more and more of refractors, which forced me to think about smaller scopes and few accessories and i forgot about the big scopes, and last year i also bought 10" RC but i never took it out of the box as i can't use it yet, now i am not sure if i use that RC will i go back to Newt at all, and i don't want to have headache as well with RC, good i bought that Truss design which has like the primary mirror independent from the focuser which is making collimation easier, but not sure how and which collimator really, and many i saw just changed the stock focuser, which means the collimation will be affected for sure if i change, but i won't use it until i am ready [my mount can't handle it yet without enough counterweights]. Back for this main topic, i remember once when i tried my 6" F/4 with almost as much collimation close i can get the stars still weren't round by edges, i don't know if that was the collimation or the back focus or unbalancing and guiding issue or all of them, i hate to deal with so many issues at once and still can't fix it completely perfectly, in 2021 was very bad year for me, and last year 2022 i was busy only to buy stuff before all prices and items gone or changed, now this year i can return back to imaging with all what i have, just need to make sure i have all tools i need rather than go out many nights and only dealing with issues more than imaging itself, wasted few years already so enough. Hi Tareq, No I get it. I have a couple of refractors myself but I still love my large newts. I’m just a plain old newt guy I guess. Your RC sounds like fun! I have heard they can be challanging to get collimated but once they are they hold quite well I guess. I wish you the best on it! Dale Like

15.85

Dale Penkala

#...

Tareq Abdulla:
Dale Penkala:
Tareq Abdulla:
Dale Penkala:
Tareq Abdulla:
Dale Penkala:
Tareq Abdulla:
And still my GSO 6" F/4 i can't collimate nicely, i can't point out it is only the secondary mirror, but i said that because when i try to collimate the secondary part it never stay centered, in fact i force the mirror to be in center by hand and not by knobs or screws which defies the use of those knobs/screws, so i think the problem is in the holder itself and spider vanes who knows, and i can't sacrifice to buy another and facing same problem.

For now with my 8" F/5 i will use the stock mirrors, they are doing fine, i can't see them as low end or low quality, i tried few times and i got bad data but targets are there clearly and standing, means the scope is doing fine, the only worry i have is when i remove the mirrors for cleaning, i don't know how to clean those mirrors properly, i mean i have distilled water, but i don't have another tools for cleaning and i don't want to scratch mirrors or damage the coatings if they have, and i don't worry about collimating my 8" F/5, but 6" F/4 has an issue dunno what that i need to figure out then fix ASAP.

Funny you mention a 6” f4 OTA Tareq, A friend of mine had one and that bugger just wound not produce any type of acceptable stars/image! I worked on that for a little while but didn’t get to in depth with it as it wasn’t mine.

Dale

I won't give up the scope, doesn't matter if the design is bad, in fact my 8" F/5 is just from Meade a discontinued one and i got it as the last piece brand new cheaper than that 6" f/4 actually which is surprising, but if this issue is available to all or most of that GSO 6" F/4 then i have to solution but to force the collimation manually by hand somehow and glue it by tapes, i have no plan to sell this 6" or buy another one as a high end or better design.

I didn’t give up on it but it’s not mine and I’d rip it apart and start from scratch if it was mine. I have my 10” and 12” f5 newts that work quite well and my new Stellarvue SVX102 for the wider field images so no need to even mess with it, and he upgraded to an 8” f5 and is very happy with the performance of it.

Dale

If i remember correctly i think i ordered that GSO 6" F/4 by 2021, and i didn't try to play with it from scratch yet, and with few times i tested collimation i really failed, even it became worse last year when i tried to image a planet [Jupiter] which i immediately changed to my Mak and i got an amazing successful result and then i never touched that 6" again, so i am not sure when and how to do so, and my mistake is that i didn't play with my 8" F/5 enough really which will make really amazing results i am sure, hopefully this year.

Yup I get it! Its hard to go back to something you struggle with when you have good success with something else!

Dale

The point was that since i bought my second Newt of 6" F/4 then i started to buy more and more of refractors, which forced me to think about smaller scopes and few accessories and i forgot about the big scopes, and last year i also bought 10" RC but i never took it out of the box as i can't use it yet, now i am not sure if i use that RC will i go back to Newt at all, and i don't want to have headache as well with RC, good i bought that Truss design which has like the primary mirror independent from the focuser which is making collimation easier, but not sure how and which collimator really, and many i saw just changed the stock focuser, which means the collimation will be affected for sure if i change, but i won't use it until i am ready [my mount can't handle it yet without enough counterweights].

Back for this main topic, i remember once when i tried my 6" F/4 with almost as much collimation close i can get the stars still weren't round by edges, i don't know if that was the collimation or the back focus or unbalancing and guiding issue or all of them, i hate to deal with so many issues at once and still can't fix it completely perfectly, in 2021 was very bad year for me, and last year 2022 i was busy only to buy stuff before all prices and items gone or changed, now this year i can return back to imaging with all what i have, just need to make sure i have all tools i need rather than go out many nights and only dealing with issues more than imaging itself, wasted few years already so enough.

Hi Tareq,
No I get it. I have a couple of refractors myself but I still love my large newts. I’m just a plain old newt guy I guess.
Your RC sounds like fun! I have heard they can be challanging to get collimated but once they are they hold quite well I guess. I wish you the best on it!

Dale

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