Taking darks won't keep shutter closed


I’m starting here with this since it’s the software I use to capture darks. I haven’t made any in several months but need to make some of a different duration. When I try to take them, the shutter on my Atik 383L+ doesn’t stay closed and I get a picture of stars. “Darks” is selected as frame type. When the sequence starts I can hear the shutter open. It used to stay closed when I made darks. I have upgraded to the newest Atik drivers.

I’ve uploaded a log where I only connected to the camera and tried to take a single 10sec dark frame. The resulting image had stars present indicating the shutter didn’t stay closed.

Thanks for any help.

sg_logfile_20160731205457.txt (64.7 KB)


You will need to enable logging in the camera driver and collect a camera log file. This should show if the camera driver is getting a StartExposure command with the exposure type set to dark or not.

It should also give some clues about the failure on the LastExposureStartTime command.

Atik upgraded the camera drivers, including the ASCOM driver, a couple of times recently and there were some issues, maybe there still are.

Chris R


I turned on the logs for the Atik ASCOM driver and took a dark sub. Here are the lines in the log:

21:45:25.747 StartExposure Duration 10, Light False
21:45:25.747 StartExposure: bin 1,1: subframe 0,0:3354,2529: high priority False, amplifier switched-True, set dark mode TrueStartExposure, started

I’ve attached the full log as well. I took a bias frame and the result was the same. Maybe I’m reading it incorrectly but it appears that SGP is sending the dark command but the driver is not setting the camera correctly?

Also, the LastExposureStartTime reference in the log is total gibberish (at least to me):
21:45:48.436 LastExposureStartTime get 〲㘱〭ⴸ㈰〠㨴㔴㈺5

Ideas? Should I pass this on to Atik?


ASCOM.Atik.2145.107170.txt (10.8 KB)


Yes it looks like that. Can you hear the shutter operating? It should not be doing so. Or you could try the camera on the bench so you can see the shutter.

The camera should return an ASCII text string containing a date/time like “2016-08-02 08:15:35”. There’s a possibility that .NET string handling has interpreted this as Unicode. Do you have some special location set in your PC?

Of course (and I see that you have). It baffles me why people seem to be so reluctant to contact the hardware manufacturer’s support.


Of course (and I see that you have). It baffles me why people seem to be so reluctant to contact the hardware manufacturer’s support.

I wasn’t reluctant to contact Atik. I guess what I really meant was confirm that this appears to be an Atik problem and not SGP.



Just an update, Atik sent me an updated driver and it’s working now.