Takahashi FSQ106 CAA Takahashi FSQ-106EDX III · jacquesdeacon · ... · 12 · 749 · 10

jacquesdeacon 3.05
...
· 
Hi Everybody,

Wondered if anyone dealt with this issue before.

I am configuring my FSQ106 with an full-frame camera (QHY600). I see some flex or ‘sag’ in the system, which obviously creates some tilting issues, especially across the now bigger full-frame fov.

I culprit seems to be the takahashi CAA (camera-angle-adjuster? ) which with the now heavier image train creates some flex or sag. If I wiggle the image train I can see some movement and feel some light ‘clicking’ coming from the CAA.

As a first step I would like to try and remedy the problem before throwing money at it. Has anyone maybe encountered this and have a solution I can try?

Best Regards,
Jacques
Like
olaskarpen 1.20
...
· 
Do you have a test picture to show
Like
jacquesdeacon 3.05
...
· 
Ola Skarpen SkyEyE:
Do you have a test picture to show

I will upload, thanks for the reply.
Like
jacquesdeacon 3.05
...
· 
Test image:

NGC2040 area; Ha filter; 300s; BIN 1x1

ha_1.jpg


Corners (PI AberrationInspector)


Ha_test_corners.jpg


Eccentricity plot (PI FWHMEccentricity)

test_essentricity.jpg
Like
skybob727 6.08
...
· 
FSQ 106’s are pretty solid scopes except one, it’s the one they put a captains wheel type rotator on, not the typical CAA. It was a bad design by Tak and they stopped making that model. It had a hard time re-centering itself when you locked it back down, very not repeatable. Not sure if it was the EDXlll or the EDXllll.
Like
JohnHen 7.91
...
· 
Hi Everybody,

Wondered if anyone dealt with this issue before.

I am configuring my FSQ106 with an full-frame camera (QHY600). I see some flex or ‘sag’ in the system, which obviously creates some tilting issues, especially across the now bigger full-frame fov.

I culprit seems to be the takahashi CAA (camera-angle-adjuster? ) which with the now heavier image train creates some flex or sag. If I wiggle the image train I can see some movement and feel some light ‘clicking’ coming from the CAA.

As a first step I would like to try and remedy the problem before throwing money at it. Has anyone maybe encountered this and have a solution I can try?

Best Regards,
Jacques

*
Hello Jacques,
my system is similar: A FSQ85EDX and the QHY600. I have a tilt adapter in the image train. It took me several runs of HocusFocus and a few hours and the tilt was eleminated (2% according to ASTAP)
However: When i changed the angle with the CAA i noticed that tilt was introduced back again and i had to start from scratch with tilt adjustment. As a result, i am not touching the CAA i.e. leave the field of view at a fixed angle. That causes no problem i.e. no sag etc. and tilt, once eleminated, stays eliminated. If your CAA introduces random tilt you should have it checked.
CS, John
Like
leviathan 4.72
...
· 
·  1 like
Just get rid of the CAA, it is unnecessary adapter in your rig. Get a custom adapter straight from M98 thread of FSQ-106 to the M54 of FW / camera.
Like
jacquesdeacon 3.05
...
· 
Bob Lockwood:
FSQ 106’s are pretty solid scopes except one, it’s the one they put a captains wheel type rotator on, not the typical CAA. It was a bad design by Tak and they stopped making that model. It had a hard time re-centering itself when you locked it back down, very not repeatable. Not sure if it was the EDXlll or the EDXllll.

Thank you Bob,

I have the one below, I took mine off the scope, definitely feel some play in it.
TKP30200CAA[1].jpeg
Hello Jacques,
my system is similar: A FSQ85EDX and the QHY600. I have a tilt adapter in the image train. It took me several runs of HocusFocus and a few hours and the tilt was eleminated (2% according to ASTAP)
However: When i changed the angle with the CAA i noticed that tilt was introduced back again and i had to start from scratch with tilt adjustment. As a result, i am not touching the CAA i.e. leave the field of view at a fixed angle. That causes no problem i.e. no sag etc. and tilt, once eleminated, stays eliminated. If your CAA introduces random tilt you should have it checked.
CS, John

Thanks John,

Thats exactly what I fear will happen when rotating.  Keeping the camera at a fixed angle is an option I also considered (maybe in the intrim)... but not ideal for framing.  

Nadir Astro:
Just get rid of the CAA, it is unnecessary adapter in your rig. Get a custom adapter straight from M98 thread of FSQ-106 to the M54 of FW / camera.

Yes, I see this is probably going to be my future...  Think I will probably go the full 9 yards and replace the whole focuser assembly with CAA.  Just an expensive proposition... 

Currently looking at the PrimaLuceLab focusers (Esatto 4"), looks very nice.  The focuser uses a 'stop ring' adapter that facilitates camera rotation.  I just dont know how stable these are and if it will be another weak point for sag/flex.

ESATTO-4-inches-robotic-focuser-descrizione3-new.jpg

adapter-from-m110-to-m68-with-stop-ring-for-esatto-4.jpg
Like
skybob727 6.08
...
· 
Bob Lockwood:
FSQ 106’s are pretty solid scopes except one, it’s the one they put a captains wheel type rotator on, not the typical CAA. It was a bad design by Tak and they stopped making that model. It had a hard time re-centering itself when you locked it back down, very not repeatable. Not sure if it was the EDXlll or the EDXllll.

Thank you Bob,

I have the one below, I took mine off the scope, definitely feel some play in it.
TKP30200CAA[1].jpeg
Hello Jacques,
my system is similar: A FSQ85EDX and the QHY600. I have a tilt adapter in the image train. It took me several runs of HocusFocus and a few hours and the tilt was eleminated (2% according to ASTAP)
However: When i changed the angle with the CAA i noticed that tilt was introduced back again and i had to start from scratch with tilt adjustment. As a result, i am not touching the CAA i.e. leave the field of view at a fixed angle. That causes no problem i.e. no sag etc. and tilt, once eleminated, stays eliminated. If your CAA introduces random tilt you should have it checked.
CS, John

Thanks John,

Thats exactly what I fear will happen when rotating.  Keeping the camera at a fixed angle is an option I also considered (maybe in the intrim)... but not ideal for framing.  

Nadir Astro:
Just get rid of the CAA, it is unnecessary adapter in your rig. Get a custom adapter straight from M98 thread of FSQ-106 to the M54 of FW / camera.

Yes, I see this is probably going to be my future...  Think I will probably go the full 9 yards and replace the whole focuser assembly with CAA.  Just an expensive proposition... 

Currently looking at the PrimaLuceLab focusers (Esatto 4"), looks very nice.  The focuser uses a 'stop ring' adapter that facilitates camera rotation.  I just dont know how stable these are and if it will be another weak point for sag/flex.

ESATTO-4-inches-robotic-focuser-descrizione3-new.jpg

adapter-from-m110-to-m68-with-stop-ring-for-esatto-4.jpg

If you go that route, you may want to check these out as well. Nitecrawler focusers from Moonlight.

MoonLite Telescope Accessories (focuser.com)
Edited ...
Like
JohnHen 7.91
...
· 
Thats exactly what I fear will happen when rotating.  Keeping the camera at a fixed angle is an option I also considered (maybe in the intrim)... but not ideal for framing.


Hello Jacques,
i agree. I would be interested myself in a rotator that does not introduce tilt. But full frame at small pixel size of 3.7u and relatively fast scope at f/5 that is a very challenging combination w.r.t tilt. Hopefully, there there is some user here with an Essato or similar and can report.
CS, John
Like
BBRAUNCCP 0.90
...
· 
The Moonlite Nitecrawler is rock solid as a focuser & rotator with no backlash or looseness. the 3.5" model that goes with the FSQ106 sells for over $3000 but it's top quality & would solve your problem.

CS,
Bruce

Wow! Just realized how old the thread is! Still good info though.
Edited ...
Like
jacquesdeacon 3.05
...
· 
·  1 like
The Moonlite Nitecrawler is rock solid as a focuser & rotator with no backlash or looseness. the 3.5" model that goes with the FSQ106 sells for over $3000 but it's top quality & would solve your problem.

CS,
Bruce

Wow! Just realized how old the thread is! Still good info though.

Thanks @BBRAUNCCP, I did not eliminate my problem fully yet, but I am ‘managing’ any tilt in the system for now, which is far from ideal, but Im getting by for now.

At some stage I will take the plunge to replace the whole focuser assembly, thanks for the +1 on the Nitecrawler, they are awesome!

Regards,
J
Like
davidRosenthal 5.49
...
· 
·  1 like
Bob Lockwood:
FSQ 106’s are pretty solid scopes except one, it’s the one they put a captains wheel type rotator on, not the typical CAA. It was a bad design by Tak and they stopped making that model. It had a hard time re-centering itself when you locked it back down, very not repeatable. Not sure if it was the EDXlll or the EDXllll.

It is the FSQ-106ED, the model that came after the Fluorite model.  I never used the Captains Wheel and had installed a CAA on it instead.  I used that for many years without issue.  When I moved to larger format sensors I started to notice sag in my images represented as tilt.  As an experiment I removed the CAA and the bad corner was gone.  In order to get image orientation back I installed a WanderAstro WandererRotator Pro.  It is amazing and guaranteed not to introduce any tilt.  I have used a few times now and am 100 satisfied with it, so much I picked up the new WandererAstro Flat Panel V4-EC

Here is my baby :-)   I am the third owner (have had it for close to 12 years) and other than the CAA this has been an amazing instrument. 

IMG_1956.JPG
Edited ...
Like
 
Register or login to create to post a reply.