Autofocus with a DSLR @ fl2000 help please


#1

Greetings,

Recently my filter wheel died so I went back to using a DSLR to image. Wow what a change but I digress.

The scope is a 10" Ritchey Chrieten (2,000 mm) and the camera is an un modded Cannon 100D resulting in about .44 as/px. The focuser is a Rigel nStep.

Once I got the spacing and focus point down manually I set out to configure AF in SGP.

I read a few things here but nothing I tried seemed to actualy work. I could not get a V could not even get a mild U more like W and Z.

I tried binning at 2x2, 3x3, even 4x4. I tried large steps (300) I tried small steps (40), I tried longer exposures, I tried different ISO but frankly nothing seemed to change.The lowest Hfr I saw all night was around 3.5.

I was hoping maybe I overlooked some setting somewhere?

Thanks


#2

Have you visually confirmed that the focuser is moving in and out like the graph says it is? Sometimes the problem is mechanical. Is there a lot of backlash? RCs are harder to focus than refractors, but I usually got decent V like curves with my RC12. But not as consistently as with my refractors.


#3

Thanks for responding.

Yes I visually verified that the focuser is moving. Also I used to use this same assembly with an ATIK383L+ and it worked quite well with that at a scale of .8 as/pixel.


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