AstroDoc1

On 24/08/2021 at 16:42, Tony Bell said:

Hi Brian did you find the answer to the adjustment on the Flattener ? 3.45mm or 5.4mm ?  Just got my FLT91 and flattener and want to fit ZWO EFW and ASI 1600 mm Pro Mono.  

Definitely 5.4mm is the starting gap then adjust from there to improve the star shapes in the corners. I use a backfocus of 56mm because I add 1 mm for the 1/3 thickness of the filters. Let me know how you make out.

Brian

I just received this scope and flattener.

is 3.45mm definitely the correct flattener gap space for a 55mm back focus with the ZWOasi2600mm camera?

I thought I read somewhere it should be 5.4mm. I need confirmation.

thanks,

brian