Optimal dark frame settings for ZWO ASI676MC

[WirthmU]

As is written in the title - any recommendations for ZWO ASI676MC?
I intended to start taking darks inside and then place the camera outside. Night temperatures here are about -10°C.

[aaronwmorris]

I would take dark frames at the warmest part of the night.

One of the known issues with this camera when taking RAW16 images is the occasional purple frame: https://github.com/aaronwmorris/indi-allsky/wiki/ASI676MC-Known-Issues If you are not experiencing a problem, then you do not have to worry about it.

If you are running in RGB24 mode, you can only take darks using the average mode. If you are in RAW16 mode, you may choose either sigmaclip or average.

[WirthmU]

Thank you for quick reply and explanations.
First question then is where can I find the settings for RGB24 vs RAW16 mode and which is better?
Second question would be because the camera will be outside here in the mountains where temperatures in summer during the night can get up to plus 20 degrees C and in the winter as low as minus 15 degrees C. What would be the optimal temperature to make dark frames?

[jimmauck]

Aaron,

Somewhat related, does auto-gain eliminate usage of darks? Or is the selected gain matched to a close dark, i.e., gain, exposure, and temp?

Thanks!

[aaronwmorris]

It does not exclude using darks. The SQL query will find the next closest exposure, gain, and temperature values to match. If the gain is 15 for an exposure and you have darks at 1, 75, and 100, the 75 gain dark should be used.

The dark processing script also now has the ability to take additional dark frames at arbitrary values if you want to fill some of the gaps using the --gains option. https://github.com/aaronwmorris/indi-allsky/wiki/Dark-Calibration-Frames

[bvalente22]

one recommendation is dark frames aren't needed in my experience. Been running the 676mc for quite some time, no problems with noise or frames. The images are quite clean even at gain 180

Brian

[WirthmU]

I have covered the lens with the plastic cap and am running the camera at room temperature. The star count varies between 6 and 12. The camera is brand new.
Would taking dark frames at RT remove the faux star counts?

[aaronwmorris]

I have covered the lens with the plastic cap and am running the camera at room temperature. The star count varies between 6 and 12. The camera is brand new. Would taking dark frames at RT remove the faux star counts?

Maybe. You could turn on Mark Detections on Image on the Processing tab and it will circle what it is detecting.