doing something about differential bending is essential.

top: supporting the focuser as close to the CCD as anyhow possible prevents differential bending.

bottom: the tube and focuser are far away from support - insufficient stability.

historic image: showing my late equipment: Gemini 41 eq mount carrying a Meade 14" SC f/10 and the 4" tmb apo;

many of my images were recorded with this SC. it was pretty good (strehl 0,96) but it had one major mistake: it was NO APO,...(-;

the scope`s setup was run with FS2 in the first place - but this drivesystem was insufficient (jumps in RA) so I changed and turned it in in favour of Pulsar.

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