OCAL collimator

Collimation Vignetting
4 replies•80 views
Menelaos avatar
Menelaos avatar
hey guys! quick question! i recenty bought the OCAL collimator for my newtonian. I am not an expert at collimation and i'm still figuring things out. Through the OCAL collimation looks decent and through a collimation cap pretty much the same! However when i take flats it looks like it has uneven vignetting. Does the vignetting necessarily mean collimation is off? (The darker side in the flat frame is the front of the scope)
andrea tasselli avatar
andrea tasselli avatar
No
Menelaos avatar
Menelaos avatar
andrea tasselli:
No

I appreciate your reply but can you be a little bit more helpful than just a simple “no”? “No” means that i was right, uneven vignette does not mean bad collimation?
andrea tasselli avatar
andrea tasselli avatar
Yes, no means exactly that.
Tony Gondola avatar
Tony Gondola avatar
Menelaos, I see the same thing in my flats. I've checked collimation and it's spot on. There are a lot of things that can effect flat frames other than fall off so as long as your calibrated lights look good I wouldn't worry about it. I think a lot of times, looking at your flats frames is a mistake it can cause a lot of trips down the rabbit hole for no reason!
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