I have a question / concern regarding the use of my recently-acquired GSO Coma Corrector. I'm using it with the SW 10" collapsible. The CNer from whom I purchased it graciously included a high-hat 2-1.25" adapter that enabled me to use it without the 19mm spacer (although I do have the spacer).
At first, this setup worked fine, but it seems like all of a sudden the backfocus is not nearly enough and I have to back the CC out of the focuser an inch or more to find the focal point. I've tried resetting the collimation on the primary mirror from scratch three times but this made no difference. I tried adding the spacer but it just made the problem worse.
Is this normal? It seems like I have to slide it out a little bit more every time. And doesn't backing it out increase the added magnification?
Thank you for any info / advice you can offer.