Seite 1 von 1

Some problem with OmegaCam@VST calibration

BeitragVerfasst: Freitag 26. Februar 2016, 01:49
von oleg
Hello,
many OmegaCam@VST calibrated frames has one problem: some chips are more dark.
Look at my attached picture: chip #31 (top right corner) is more dark.

Any ideas?

Bild

Re: Some problem with OmegaCam@VST calibration

BeitragVerfasst: Freitag 26. Februar 2016, 12:28
von oleg
Also, see calibrated frame with sky subtraction (Subtract a constant sky) from filter NB_659 (or Ha):

Bild

Re: Some problem with OmegaCam@VST calibration

BeitragVerfasst: Freitag 26. Februar 2016, 21:40
von mischa
Hi Oleg,

your screenshots (or whatever you are uploading) do not make it into the forum (and they didn't appear attached to the email you sent yesterday, either). Maybe a file size issue?

Re: Some problem with OmegaCam@VST calibration

BeitragVerfasst: Freitag 26. Februar 2016, 23:39
von oleg
Also, see calibrated frame with sky subtraction (Subtract a constant sky) from filter NB_659 (or Ha):

Bild

Re: Some problem with OmegaCam@VST calibration

BeitragVerfasst: Samstag 27. Februar 2016, 00:26
von mischa
well, since we don't see the images: can you check whether that chip is already darker after the first calibration step ("calibrate data")? If so, how does the flat of that chip compare to that of the other chips? maybe it's saturated.

mischa

Re: Some problem with OmegaCam@VST calibration

BeitragVerfasst: Samstag 27. Februar 2016, 01:37
von oleg
Hmm... Do you see this image?

Bild

Re: Some problem with OmegaCam@VST calibration

BeitragVerfasst: Samstag 27. Februar 2016, 01:42
von oleg
Uncalibrated frame:
Bild

Re: Some problem with OmegaCam@VST calibration

BeitragVerfasst: Samstag 27. Februar 2016, 01:45
von oleg
Chip #31 is already darker on original (raw) uncalibrated frames.