Quote:
Originally Posted by gregbradley
I have had 2 FSQs, the 106N and the 106ED. The focuser on the 106N is like a rock and very strong and the focuser lock screw worked really well without shift. For some reason Tak did not use that excellent focuser on the 106ED and put the CAA on it as well plus the silly captains wheel to rotate the focuser.
There are numerous threads of those who experienced flex with that setup.
The FSQ106ED I had did not and I used a FLI Proline 16803 and FLI Filter wheel 4/5 and a guide scope and it worked just fine.
There are screws under the focuser that can be tightened to put more pressure on the focuser rail and it reduces flex.
The 106ED111 I thought had a solid section with no captains wheel and I thought no CAA or maybe I have that wrong and it has no captains wheel but has the CAA in its place. The CAA is handy and usually it does not flex.
I would go a solid adapter tube from the CAA to Atlas/MMOAG/CFW/Proline.
You could double check with John Gleason as he uses an FSQ106ED and Atlas I am pretty sure. I don't know if he uses a MMOAG though.
If you do use a guide scope it should be attached to the OTA not the OTA's rings as that can cause differential flexure.
AP has a special Baader vario finder that is used for autoguiding that attaches to the scope and is well supported to prevent flex. Some use it to guide their Honders.
Greg.
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Thanks Greg, All valuable info that I'll take into account.
The draw tube is what is flexing, no doubt more tension would help, but that's flex against the actual main force applier, i.e the bottom focus mechanism, so side on, I'd assume even worse flex. It's not horrific, probably less than 0.4mm, but with an inbuilt corrector lens and a large CCD it's not something I want to even be a "potential issue". Note, this is even with the focuser racked fully in and locked (as per instructions).
I like the Atlas, but the adapters needed to replace both the Focuser and CAA are pretty huge and I still want some ability to use it for visual "sometimes".