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Asi585//PDS150

Equipment Auto-Focusing Help Needed
6 replies•222 views
Orfanidisharis avatar
Orfanidisharis avatar
Good morning,I have an issue with focusing and I am really struggling with it.i have checked the backfocus,I have tested the camera with the extra spacers but always my focus is a bit off.

also I have collimate my telescope and the laser seems to be ok.

what is happening?any guess?

(also I use comma corrector.)
andrea tasselli avatar
andrea tasselli avatar
The question is a bit too generic. Give examples (images) and also state whether you can't reach focus or it's a question of quality of focus at best focus. Also, please, state what backspacing are you using and what coma corrector. Then we might be able to help.
Orfanidisharis avatar
Orfanidisharis avatar
I use the SW 1.0X2" comma corrector
the backspacing that i measure is 55mm (from the flange of comma corrector until the sensor of the camera ) 
the focus it’s barely ok,if you see the stars I think that are big enough
andrea tasselli avatar
andrea tasselli avatar
There might an issue with collimation, more evident in the Crescent Nebula shot but otherwise I can't see anything obviously wrong with the focus, other than you might been having poor seeing. Try to shot the NP (Polaris) without tracking taking 5s integration and trying to achieve as tight stars as you can, assuming you are focusing manually. Then we'll see what, if any, are the issues with focus.
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Orfanidisharis avatar
Orfanidisharis avatar
Thank you my friend.I will try again
donsinger avatar
donsinger avatar
The triangular star shapes in the Crescent shot looks like pinched optics-I would loosen the primary mirror clips a tad….just enough to get a piece of paper undet

Don
Orfanidisharis avatar
Orfanidisharis avatar
I searched about it and indeed I have the same "egg shape" stars.

i will sit down today to give a try

i have to say,that I am scared of untightened  the primary mirror…but I will do what I must 


thank you in advance!