Peculiarities of imaging well from a 2nd floor wooden deck [Deep Sky] Acquisition techniques · Rick Evans · ... · 14 · 782 · 0

revans_01420@yahoo.com 1.51
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Unfortunately my yard has a very poor view of the sky.  But from my 2nd floor wooden deck which opens off of my office I have a great unobstructed view of most of the sky.  For this reason I have had to deal with the peculiarities of imaging on this surface. These are my accomodations to make this work:

1. I am never physically present on the deck during an imaging run while guiding is going on and subexposures are being gathered

2. I control my Paramount MYT/SVX140 f6.8 with ZWO ASI6200MC camera, and Esprit 80 f5 guide scope with ZWO ASI178MM guide camera from indoor, in my office which opens onto the deck used for imaging.  This could be done wirelessly but my solution is to run 10ft cables from the scope, guide scope, focus motor, dew heater, mount and cameras from the rig on the deck into my office.  I bring them in through a screen door so that mosquitoes don't come into the house.

3. My main difficulty is in getting a very precise polar alignment using PoleMaster because I have to physically be on the deck to adjust the altitude and azimuth knobs on the mount.  If I move around the deck the polar alignment will shift by as much as 5 arc minutes.  So I had to learn where to put Polaris in the PoleMaster spinning circle so that it is centered when I am inside the house.  But it will be off-center as soon as I walk out onto the deck anywhere near the telescope/mount rig.  This can be done with experience but is a bit of an art.

4. I use anti-vibration pads that are high quality, putting them under each tripod leg of the mount.  As long as I am polar aligned within 5 arc minutes of the pole I can achieve consistent guiding well under 1 arc second and I've seen RMS values well under 0.5 arc seconds with my setup.

5. I usually stop imaging if my autofocuser cannot produce consistent FWHM star values of under 2.5 arc seconds during the course of an imaging run. 

6. I have to set up my rig every night from scratch which has advantages and disadvantages.  On the plus side my equipment is stored inside the house.  On the bad side, I have to setup and takedown the rig for each session and have to polar align each session.  Because of the time involved I do not use the T point system the Paramount MYT was designed for.  I prefer to use the necessary SkyX Pro software to park, unpark, home, and track.  I use Astrophotography Tools and PHD2 for scope and imaging/guiding control linking it to SkyX via ASCOM and Optec 3rd Lynx drivers.  This is the reason I use PoleMaster for polar alignment. 

I know that some of what I do is somewhat specific to using a Paramount MYT but would be interested in what the experience of others has been imaging from surfaces like a wood deck or flat rooftop etc.  I would also be interested in your thoughts in general.  Ideally, since my skies are Bortle 5-6 I should drive to a dark sky site and avoid the deck issues.  However, I'm not able to travel these days and am very much confined to my house and yard where my astronomy hobby is concerned.

Rick
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Pistachio_Enjoyer 2.15
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Interesting situation you have there. I also used to image from a second floor balcony, though I would just leave my equipment outdoors for the most part. Might I suggest getting a telegizmos 365 cover so that you can leave your equipment outdoors? I own one and have been able to leave my equipment outdoors for extended periods of time without worry of my equipment burning under the sun.
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revans_01420@yahoo.com 1.51
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If several days in a row of good weather for imaging is forecast then I will leave the rig setup and I cover it with (would you believe it...) five heavy duty tarps. I do this because the rig is reasonably expensive and I don't want water to get into the optics.   This did happen one night I was imaging and went to bed at 2am leaving the rig ticking off subexposures only to wake at 6am and find the deck engulfed in a seething fog whose moisture got inside everything.  I will look up telegizmos 365 and see if it looks practical for me.  

Rick
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andreatax 7.76
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As other have suggest you should really think about leaving everything outside under properly designed covers. I have done that for more than 20 years (in backyard) and the instruments are none the worse except for the obvious spot of rust and critters galore, mostly spiders and their webs. Nothing too terrible.

As for the peculiar situation you find yourself in I can sympathize as I had the same problem in my previous home, having to image at the edge of a wide balcony. In my case, however, I stayed there all the time when imaging. That was before all the modern gizmos for remote imaging were invented or made available at a reasonable price.
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Staring 4.40
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Hah, I thought I was the only one doing something like this. I have a wooden deck in 2nd floor, too (but on a concrete balcony). There is another, protruding balcony below and I have to close the patio screen above it to prevent heat currents from messing up my seeing. Anything involving manual manipulation is a chore because when I need to leave the deck to take images. A 5-minute collimation or tilt adjustment job becomes an hour easily if I’m not up to my game. I‘ld so love a scope with motorized collimation (like the Meade RCX but with better electronics).

Amazingly, my 10M mount is able to model the surface movements well enough to be able to do unguided imaging at 1600mm FL for 300s. But I need to use a 90-point-model and it will invalidate within a week, so I mainly do guiding in addition.

I have my stuff outside under Telegizmos covers and it has worked perfectly for 3 years now. No bugs, no hardware problems, just a bit of dust. I do shut off everything automatically once 40°C are reached under the cover, heat it very slightly to prevent dew (5° above dew point) and have ventilation going if the inside temp is not below ambient.

Moving everything to the garden is not an option because that would leave only targets above 60°. I‘m thinking about having a remote setup but shirking the travels involved should anything need adjustments.
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afd33 4.65
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I image from my deck (20x20 foot or so) too. Mines on the first floor though, but still about 3 feet above ground. 

I encounter a lot of the same things you do. If I step anywhere on the deck, there’s vibration. I use an ASIAIR Plus, so generally I sit in my bedroom that’s right inside and control everything from there. If I’m awake I’ll watch the meridian flip through the window. 

For polar alignment, first I get it pretty close. Then it depends on the season, in the summer I walk to the very edge of the deck, stand still, take an exposure. In the winter I’ll actually go back in the house (it’s only like 7 feet away) and do the same. Then walk back out, adjust, walk away, repeat. It’s tedious and takes longer than if I could just stand next to it, but it’s what works. 

Currently I set up from “scratch” almost every night. If I see no chance of rain I’ll leave it up. Scratch in quotations because I have a small enough set up that with a little tilting and maneuvering I can leave it completely together and fit it through the patio door. Just plug in an flip two switches. Soon I suspect I won’t be able to do that, as I have an EQ6R Pro now too. Once I get the tripod for that, I’m guessing that’s going to be a bit heavy to do the same. 

Two other issues I have is lights from passing cars. I used to only have a view north and east, and a rural highway runs right next to my house. So cars with their rights on would sometimes add gradients to my subs.

The other issue, now solved, was trees blocking a lot of my view. North and east my roofline makes me have to image above about 30 degrees. But on a compass I used to have no sky from about 110 degrees through about 310 degrees nearly all the way to zenith. So I could only image things really to the northeast. I got some trees taken down (one was dying and three were too close to the house anyway) and as a side benefit I have more sky. It’s clear starting at about 270 degrees all the way through to about 200 degrees and a lot more clear sky directly overhead. 

P.S. sorry for writing a novel. Thanks for reading if you got this far.
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SteveInColorado 1.43
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+1 for the Telegizmos 365 cover.  I image from our second floor deck (Trex, not wood).  I generally leave everything set up except the mountside miniPC and extension cord.  I'll occasionally disassemble the setup and bring it in if we're going for an extended vacation or if winds over 50 mph are predicted.

For polar alignment, I set NINA to use the highest gain and binning and fastest exposure (4-5 seconds) that will plate solve.  I generally lose one exposure as I step away after an adjustment, but it's not a big deal.
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FraaRog 1.20
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I often set up on my third-floor "rooftop deck," which is tile on a wood frame house. Like others, if I move around, everything goes wonky. I use an NUC to control everything and I remote desktop into it, either from my desktop in my office on the second floor, or a laptop on the deck with me (like when I polar align). I can get polar alignment that survives me moving around afterwards down below 1 arc-minute, though I wait and run the Guide Assistant in PHD2 from my office. I have an Astro-Physics 1100GTO AE, and my personal best is about three hours at 0.17 arc-seconds total RMS (it made me smile). It's interesting to watch "house settling events" as things cool off, but eventually things stabilize and tracking is excellent.

I will occasionally leave everything set up for a few nights if the weather looks promising; I use a Telegizmos cover. The "trick," since I live near the coast where it can be fantastically dew-ish, is to not cover up when things are wet. I use a dew strap hanging from the dovetail inside the cover to keep it warmer in there, which seems to keep it dry if it starts out dry. I always bring in the NUC, even though I have it in an enclosure with a desiccant box. The corrector plate is dry as I use a ring & shield on it, so the first thing I do is cover it when I stop imaging.

When the weather is not cooperating, I break everything down and bring it inside to a landing leading out to the deck. The mount and scope are heavy enough that I have to break it all down to move the gear in/out.

Using the laptop and sitting still while on the deck seems to be fine in my case. Once I'm ready to start imaging, I move inside for the final focus run, start guiding, and off I go. Eventually I will probably seek out a managed remote site, but I enjoy tinkering right now so that moment is still in the future.
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tomtom2245 1.20
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I'm wondering if turning one of the deck support posts or railing posts into a pseudo pier would help your situation at all. On my old deck, I could pull the cap off of the top of the railing 4x4s. If you could attach a mounting plate to the top of one of these posts, would that provide you anymore stability? That way instead of taking a tripod out on the deck, you just attach the mount head to one of the posts.
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justasecond 0.00
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My observatory is in my attic.  My house is brick with a widows peak.  I cut a hole and installed a nexdome about 2 years ago and have had good luck.  I am fortunate to have load bearing walls crossing directly near the mount.  My house was built from old warehouse beams in 1940.   It has 8" floor joists in the attic and 10" in the main floors.  The structure is brick.    My default exposures are about 180s for most but can do 300s guided images using my Celestron CGX and a Meade 10 SCT.  I just purchased a better mount and upgraded my pier.  I will be running Paramount MX6 and Delta Rho 350 on Piertech pier.  This rig is also one we will take out west when we camp to do some images.  I'm anchoring everything using aluminum flat bars and plate to the foundational walls.  I will have to report back on my success.   I felt I was having good results with my Celestron mount and home made pier that is over 10 ft tall when extended.   Crazy project but having so much fun.
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chrissulyma 0.90
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Rick Evans:
3. My main difficulty is in getting a very precise polar alignment using PoleMaster because I have to physically be on the deck to adjust the altitude and azimuth knobs on the mount.  If I move around the deck the polar alignment will shift by as much as 5 arc minutes.  So I had to learn where to put Polaris in the PoleMaster spinning circle so that it is centered when I am inside the house.  But it will be off-center as soon as I walk out onto the deck anywhere near the telescope/mount rig.  This can be done with experience but is a bit of an art.

4. I use anti-vibration pads that are high quality, putting them under each tripod leg of the mount.  As long as I am polar aligned within 5 arc minutes of the pole I can achieve consistent guiding well under 1 arc second and I've seen RMS values well under 0.5 arc seconds with my setup.


I currently image from a wooden deck on the ground floor, about 3' off the ground. Vibration pads and the overall weight of the AVX mount have kept ruined shots from transient events (patio door opening/closing, even the washing machine in the basement used to cause issues on lighter mounts) to a minimum, but I agree with the issues about polar alignment and stepping on the deck. Unfortunately, my best practice has been to adjust, step inside, check the current alignment, step outside and adjust, rinse lather and repeat. I've cut down my polar alignment time to maybe 5 minutes max, using SharpCap's alignment feature, so not a huge deal for me. I am usually aligned inside of 20 arc seconds by the end of it.
Rick Evans:
6. I have to set up my rig every night from scratch which has advantages and disadvantages.  On the plus side my equipment is stored inside the house.  On the bad side, I have to setup and takedown the rig for each session and have to polar align each session.  Because of the time involved I do not use the T point system the Paramount MYT was designed for.  I prefer to use the necessary SkyX Pro software to park, unpark, home, and track.  I use Astrophotography Tools and PHD2 for scope and imaging/guiding control linking it to SkyX via ASCOM and Optec 3rd Lynx drivers.  This is the reason I use PoleMaster for polar alignment.


I'm also required to tear down at the end of every night (small patio, which my dogs go out from to do their business, BBQ, unfenced yard, etc), but my set-up is fairly compact, so no big issues there (just lugging 70lbs of mount and scope from my office to the patio). The only real drawback I've had from this so far has been waiting for the scope to achieve ambient temperature. 
Rick Evans:
2. I control my Paramount MYT/SVX140 f6.8 with ZWO ASI6200MC camera, and Esprit 80 f5 guide scope with ZWO ASI178MM guide camera from indoor, in my office which opens onto the deck used for imaging.  This could be done wirelessly but my solution is to run 10ft cables from the scope, guide scope, focus motor, dew heater, mount and cameras from the rig on the deck into my office.  I bring them in through a screen door so that mosquitoes don't come into the house.


This is exactly how I run my setup, too. I run 10-foot cables from the mount through my screen door to the laptop, sitting on my dining room table. 

Glad to know I'm not the only one doing things this way!
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SchwarzBlack 0.90
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Rick Evans:
Unfortunately my yard has a very poor view of the sky.  But from my 2nd floor wooden deck which opens off of my office I have a great unobstructed view of most of the sky.  For this reason I have had to deal with the peculiarities of imaging on this surface. These are my accomodations to make this work:

1. I am never physically present on the deck during an imaging run while guiding is going on and subexposures are being gathered

2. I control my Paramount MYT/SVX140 f6.8 with ZWO ASI6200MC camera, and Esprit 80 f5 guide scope with ZWO ASI178MM guide camera from indoor, in my office which opens onto the deck used for imaging.  This could be done wirelessly but my solution is to run 10ft cables from the scope, guide scope, focus motor, dew heater, mount and cameras from the rig on the deck into my office.  I bring them in through a screen door so that mosquitoes don't come into the house.

3. My main difficulty is in getting a very precise polar alignment using PoleMaster because I have to physically be on the deck to adjust the altitude and azimuth knobs on the mount.  If I move around the deck the polar alignment will shift by as much as 5 arc minutes.  So I had to learn where to put Polaris in the PoleMaster spinning circle so that it is centered when I am inside the house.  But it will be off-center as soon as I walk out onto the deck anywhere near the telescope/mount rig.  This can be done with experience but is a bit of an art.

4. I use anti-vibration pads that are high quality, putting them under each tripod leg of the mount.  As long as I am polar aligned within 5 arc minutes of the pole I can achieve consistent guiding well under 1 arc second and I've seen RMS values well under 0.5 arc seconds with my setup.

5. I usually stop imaging if my autofocuser cannot produce consistent FWHM star values of under 2.5 arc seconds during the course of an imaging run. 

6. I have to set up my rig every night from scratch which has advantages and disadvantages.  On the plus side my equipment is stored inside the house.  On the bad side, I have to setup and takedown the rig for each session and have to polar align each session.  Because of the time involved I do not use the T point system the Paramount MYT was designed for.  I prefer to use the necessary SkyX Pro software to park, unpark, home, and track.  I use Astrophotography Tools and PHD2 for scope and imaging/guiding control linking it to SkyX via ASCOM and Optec 3rd Lynx drivers.  This is the reason I use PoleMaster for polar alignment. 

I know that some of what I do is somewhat specific to using a Paramount MYT but would be interested in what the experience of others has been imaging from surfaces like a wood deck or flat rooftop etc.  I would also be interested in your thoughts in general.  Ideally, since my skies are Bortle 5-6 I should drive to a dark sky site and avoid the deck issues.  However, I'm not able to travel these days and am very much confined to my house and yard where my astronomy hobby is concerned.

Rick

I also image from my 15' high 20x20' wood deck made up of 2x12, 6x6 legs, and a 2x6 surface, I too live in a bortle 5 area.   As you mention, polar alignment is an art on a wood deck, especially mine which is completely open underneath and supported only by the 4 corner legs and 2x12 beam which is bolted to the brick house.  I use the polar align feature in my asi air after using the polar scope to polar align.   My tip is to run polar alignment and measure the offset while you are not standing on the deck and make note of the mounts error. Then run it again while sitting next to your mount.  Because you pre polar aligned with the polar scope, it should already be somewhat close and you can now compensate for the flexure you created by getting close to the mount.

The flexure of my deck threw me off at first I and I thought it would be impossible, now I can polar align in 20 minutes easily. I will often leave my scope covered and image multiple nights if I have a chain of clear nights.  As long as Im not on the deck, I have no problems imaging 900s exposures all night. The asi air makes it very easy to control wirelessly.
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SchwarzBlack 0.90
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Rob Fennell:
My observatory is in my attic.  My house is brick with a widows peak.  I cut a hole and installed a nexdome about 2 years ago and have had good luck.  I am fortunate to have load bearing walls crossing directly near the mount.  My house was built from old warehouse beams in 1940.   It has 8" floor joists in the attic and 10" in the main floors.  The structure is brick.    My default exposures are about 180s for most but can do 300s guided images using my Celestron CGX and a Meade 10 SCT.  I just purchased a better mount and upgraded my pier.  I will be running Paramount MX6 and Delta Rho 350 on Piertech pier.  This rig is also one we will take out west when we camp to do some images.  I'm anchoring everything using aluminum flat bars and plate to the foundational walls.  I will have to report back on my success.   I felt I was having good results with my Celestron mount and home made pier that is over 10 ft tall when extended.   Crazy project but having so much fun.

very cool, any leaking issues? I would love to do this at my house. Does the heat from the roof cause problems?
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justasecond 0.00
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Hi Wes

Very kind of you to say.  I put a pic on astrobin of my old setup.  With the original pier,  celestron cgx-l  and my Meade 10".   The heat has not been a big problem.  I open up about 2 hours before I image to let it all come adjust to the ambient.   I have not had any leak problems with the exception of when it was really windy and powdery snow get a bit blown in around the shutter.  Nothing really to speak of.   I am designing a dome of my own now that  I see how it all works.  The NexDome is a fine dome but I don't feel like the windlass system is up to snuff or the shutter in the event of high winds.  Started thinking about how roller coaster wheels work and am using this to design a dome that cannot be lifted with wind.   I am sure its not perfect but its my space and I really enjoy it.   I am about to install the paramount Mx and it will be a great mount to that won't hide anything.  I will keep you posted.  

Rob
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revans_01420@yahoo.com 1.51
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Over the past few years I've tried imaging at many different focal lengths on the wooden deck and depending on the focal length I've sometimes been able to use tracking alone after a good polar alignment.  It is possible to take 2-3 hr exposures with my C9.25 at f/6.3 butit does require guiding and I find it best to keep sub-exposures to 30 seconds each.  I have to physically leave the deck after the first couple of subs are done and I check on the progress of focus and guiding accuracy from indoors using 7x35 or 8x21 binoculars, viewing my laptop screen.  

I only use the C9.25 for small galaxies and mediumsized  galaxies and small planetary nebulae.  So, most of the time I use my perhaps favorite telescope, a Takahashi FSQ106-N Petzval type refractor at f/5.  This is a pretty fast scope and at a focal length of 528mm it does not require guiding as long as my polar alignment is good and I keep sub-exposures to 30 seconds.   I can have a total imaging time as long as I want.  Again, I have to physically leave the deck after the first couple of subs are done and check on subsequent results and focus using binoculars from indoors.

I'm speaking about the winter here.  In summer I can put my laptop just inside a sliding screen door that leads to the porch and telescope.  So In summer I can be indoors for everything except polar alignment.

There are advantages and disadvantages to keeping subexposures short at 30 seconds.  The advantages are that a plane is only going to ruin one exposure or two at most.  Also, in post-processing you can correct better for blown out galaxy cores or nebula cores as in M42.  Also, I find that stars are rounder than with subexposures that are minutes long, even with guiding.  The principal disadvantage is that using a large format camera, a lot of memory is taken up and processing time is increased.

Rick
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