KAF-8300 BIAS ISSUES

[gloicq]

Hi there,

I'm getting crazy with PI and hope that someone can help me here...let me explain...
I went to Tenerife last month and I've taken some wonderful pictures but cannot calibrate them and I don't know why !

I've been using PI since 1 year, always used the same processes and everything was working fine.
This time, PI gives me really dark et degraded pictures after calibration. I discovered it was because of the bias so I made new Masters bias (2x with my process icones and 2x with a friend's process icones) but didn't work.

There's a picture without calibration (just a STF) :




And a picture with calibration (bias, dark and flat)




Any idea ?

[vicent_peris]

Hi,

Try to inspect the calibration images in Blink to see if there's anything wrong in any of the frames.


Best regards,
Vicent.

[Andres.Pozo]

You can also check if the FITS of the calibration and light frames use the same coordinate origin (up-bottom or bottom-up). BatchPreprocessing has a checkbox for configuring this.

[gloicq]

Hi Andres and Vicent !

Thanks for your answers !
Well, what I really don't understand is I first tried to use de same bias that I use always and it didn't work.
I tried also to make new master bias 4 times and nothing worked...
About the coordinate origin, I don't think the problem comes from that. There's no auto-flip with the Moravian G2...

So bad :-/

[vicent_peris]

Hi,

I would need to take a look at your data set to be able to give you any further help.

Best regards,
Vicent.

[MikeOates]

Is it possible that the bias is being subtracted twice? This can happen if you calibrate the darks separately, but leave the option to calibrate the darks ticked when calibrating the lights.

Mike

[derrickf]

I have seen similar issues with QSI KAF8300 based cameras when the lights and calibration frames are obtained using different readout speeds/modes. If you are using a QSI camera or another brand that supports fast and normal readout modes it may be worth checking this.

HTH

Derrick