Plate Solve and Autofocus with OSC Camera

Focus and plate solve work great for me except with my ASI294 OSC camera. Even all-Sky plate solver times out. I have been using a 1x1 bin and noticed in the documentation 2x2 is generally recommended. Does using 2x2 with a Bayer matrix camera provide more reliable ps and focus results? Can’t check myself for a couple weeks when my new mount arrives.


There is not problem to use OSC for focus or plate solving, just more difficult due to the reduced signal, so its matter of your settings.

OSC camera have resolution different from normal calculation due to the bayer matrix … if you want to use AllSkyPlateSolver you must edit the right focal lenght in Voyager to avoid long time on resolution or timeout, just few unit of difference in focal lenght mean problem on solving. You must solve before and reading the exact focal lenght and save it.

For plate solving better to not use All Sky Plate Solver is not really fast, use it for Blind.

2x2 bin remove the bayer matrix so you fastening the process and have better data to use for plate solving (no matrix with black row col)

Remember to download the right index for ASPS related to your setup.

All the best

Actually the ASI294 has an idiosyncrasy, it still produces colour images when it is binned at least a 2X2!

I use a 294MC Pro and I have not had issues with plate solving or focus. To use ASPS, as Leonardo suggests, correct focal length is very important. I use the settings assistant in ASPS to solve an image online to get the image scale and calculate the focal length accurately to put in to Voyager. With a C925 SCT and reducer for about F7 and an F5 refractor I have had reliable plate solving with 5 second exposures and focus has just worked.

Thanks! The issue has become somewhat moot as I just sold the 294! But I will follow that advice with my new OSC camera whenever I can get clear skies again. I was actually off on focal length. The calculated fl for my telescope/flattener combination is 871mn and I’d entered 858 mm. That still wouldn’t explain focus issues, but the 294 was the only camera I’ve had these issues with and maybe they’ll go away with the camera!

Wayne, which is the issue with the focus ? I dont know which kind of autofocus you are using in Voyager but if is related to RoboFire can be only a settings problem, really difficult is related to Camera.

Thanks! I was using Robofocus, which works superbly with all my other cameras. With the 294 there was just no star showing up in the focus window. Process would run through and no star. I did start pretty well in focus, and I had been able to do Vcurve ok. So maybe I changed settings in an effort to get ASPS to work that affected focus. But I’m not going to worry any more over it, looking forward to using my new camera with no problems. :grinning:

Wayne,remember to point the right star before doing the first light wizard for the new camera and for next vcurve if needed ( Green button “Point closest focus star with RoboStar”) or nothing work:

Also CMOS have different signl than CCD and also a bad pattern noise, so remember to choose if necessary a different magnitude range of the focus star:

All the best

Thanks for the tips and reminders Leo! It’ll be at least a week until I get the chance, but I’ll let you know how it goes. This camera is the new 16-bit QHY268C and the dark frames look very clean so hoping it will be smooth sailing.