Coma Correctors basics please

The more I learn the more it costs me!

I have read numerous threads here on coma correction and find myself confused. Is there one you just put in the focuser and it works transparently or do I need my slide rule every time I change an EP? What about moving between 2" and 1.25" EPs? I do all visual push-to viewing and tend to change my EP's MANY times in a nights viewing. I have been working really hard to get collimation down pat and studied the virtues and trappins of various WF EP's - bought one - and now I see all these comets in ALL my EP's that I never really noticed or cared about before.

As an aside, anybody else relate to the process?

>> Is there one you just put in the focuser and it works transparently or do I need my slide rule every time I change an EP? What about moving between 2" and 1.25" EPs? I do all visual push-to viewing and tend to change my EP's MANY times in a nights viewing. I have been working really hard to get collimation down pat and studied the virtues and trappins of various WF EP's - bought one - and now I see all these comets in ALL my EP's that I never really noticed or cared about before.<<

Paracorr.

They are 2" only these days, and tunable for more specific focal ratio coma correction. Some of the better commercial light bucket builders strongly recommend putting one in the focuser, and leaving it there. Optical guru's do the same, so as to yield the largest possible diffraction limited field in view in the focuser.

It is immediately obvious to me where coma correction is and isn't being used, when peeking thru different fast newts. That's not the same as one can't live without it. But it's not subtle either.

The wider the actual field, the more coma there is to be seen.