Help! i can't reach focus with my telescope

Equipment Reflectors Coma
2 replies•268 views
Fernando avatar
Fernando avatar
Hello everyone:

I need some advice. I have a GSO 200/800 Newtonian telescope and a QHY 294C Pro. Additionaly i have a ZWO Filter drawer and also an OAG from ZWO. I've recently bought a Sharpstar 1x coma corrector. The problem is that if i insert fully the coma corrector in the focuser, i can't reach focus. So i have to leave the coma corrector partially outside the focuser. My question is if i can solve my problem with an adapter like this:


I'm hoping for some answers. Thank you!
Werner Stumpferl avatar
Werner Stumpferl avatar
Hi Fernando,
If you come in focus with an extension tube then yes. But I prefer the Baader Click Lock instead of such tubes. It can be screwed to the focuser (mostly) and it holds your corrector absolutely strong.

CS
Werner
andrea tasselli avatar
andrea tasselli avatar
Fernando:
Hello everyone:

I need some advice. I have a GSO 200/800 Newtonian telescope and a QHY 294C Pro. Additionaly i have a ZWO Filter drawer and also an OAG from ZWO. I've recently bought a Sharpstar 1x coma corrector. The problem is that if i insert fully the coma corrector in the focuser, i can't reach focus. So i have to leave the coma corrector partially outside the focuser. My question is if i can solve my problem with an adapter like this:


I'm hoping for some answers. Thank you!

Short answer: No, most likely as the CC tube is too long.
Long answer: You'd need spacers between the focuser's flange and the CC flange.
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