I'm considering purchasing a QSI683 and was wondering if the focus area of my GSO 10inch f4 would need strengthened to cope with the additional weight. I have a moonlight 2.5" focuser currently and QHY8 pro camera.
Several reviews suggest adding a steel plate or perhaps I could get a carbon tube from TS in Germany.
I've used my QSI683WS8 on my 10"f5 GSO newt - I've not seen any issues with the strength around the (Moonlite) focuser - in fact I had an aluminium doubling plate rolled anticipating there would be an issue but never installed it because I didn't notice any problems.
For what it's worth, I use the same camera with a Rowe corrector, in an old jmi 2" Crayford on the original Meade sonotube with no reinforcing, and have yet to see any credible evidence of flexure.
Cheers,
Andrew.