Atik 383L Darks


#1

I have an Atik 383L CCD. If I do Darks in the Atik softwarArtemis, I can set it so that the mechabical shutter does not open during the exposure. I would prefer to do Darks in SGP. If I set a sequence for Darks, does SGP ‘instruct’ the camera to keep the shutter closed during a Dark exposure. I ask because I did some Darks in Artemis and these were fine. I then tried Darks in SGP and found a bright area to the left of the resulting image. I have included a link to a 30 minute Dark captured in Artemis and an 8 second Dark (intended for use as a Flat Dark) in SGP. Ihope this demonstrates the issue.

Thanks

30 minute Dark

8 second Flat Dark


#2

The short answer is that SGP should keep the shutter closed, IIRC (I
used to use a 383L+). It’s not unusual to see a bit of glow along the
sides with this camera, but your 8sec dark is pretty extreme. I would
first take some 30min darks with SGP and see how those compare to those
captured in Artemis.


#3

Thanks. I’ll try some longer exposure darks in SGP. Firts though, I am going to try some 8 sec exposures in Artemis. That should be a bit quicker!


#4

Just got back from the observatory. 8 second darks with Artemis showed no abnormalities. I then went back into SGP and tried some 8 second darks there. Lo and behold they were entirely normal too. I’m not sure what was going on the other day, therefore. I had been experimenting with a new luminance panle for flats just prior to doing teh darks and I was having a lot of trouble dimming the panel sufficiently. The flats kept blowing out. I don’t know if that was the cause - if so it affected all 25 of the darks I took.

In any event, today the SGP darks looked identical to the Artemis ones.


#5

Try capping your scope. The shutters aren’t perfect and you often can get some light in that is unexpected. I try to shoot my darks at night (stray light gets into observatories during the day) and can wreck them.

Good luck!


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