Fine tuning spacing

[Lognic04 (Logan)]

Hi all!
I am using a new corrector (and reducer) with my MT-160, and i should be at the 56mm of required spacing but i'm off (see attached pics of coma).
How can i tell if my spacing is too far in or out, and how can i fine tune spacing by only a few mm's?

[peter_4059 (Peter)]

I use these in between the t thread attachments.

http://www.astroshop.eu/extension-tu...0-5-mm/p,48168

[glend (Glen)]

You can get variable spacer rings, which adjust through a range and have a locking ring. Bintel has them i think, as do other places like Teleskop-Express, Agena Astro, etc.


https://www.teleskop-express.de/shop...m-to-30mm.html

[Lognic04 (Logan)]

But also, could the optics be pinched? the triangular shape from my research seems to be pinched optics.

[billdan (Bill)]

Hi Logan,

I had these pictures saved to my hard drive, can't remember who drew them so my apologies to the author.