Author Topic: Amp Glow removal with Dark Frames issue  (Read 2073 times)

Offline Watto

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Amp Glow removal with Dark Frames issue
« on: 2016 April 16 02:12:45 »
Hello,

I have a ZWO 174MM Cool camera, it does produce some amp glow and I am trying to process it out of my images.

I am still a novice with PI and I am having issues removing the amp glow with my dark frame calibration and have tried to remove through the DBE tool but to no avail.

Can someone offer advice on settings to correct the amp glow, I have been successful in calibrating the amp glow out in another software package, but with my investment in PI I would like to streamline my processing to only PI.

I am sure it is a setting I have incorrect.

Thanks,

Watto

Offline TobiasLindemann

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Re: Amp Glow removal with Dark Frames issue
« Reply #1 on: 2016 April 16 09:19:17 »
Watto,
have you tried to deactivate the option "optimize dark frame" in the calibration process?
Maybe an example of your light and dark frame would help.
Tobias

Offline Watto

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Re: Amp Glow removal with Dark Frames issue
« Reply #2 on: 2016 April 16 20:00:35 »
Hi Tobias,

Thanks for your reply, the issue turned out to be I had activated the option "optimize dark frame". All good now.

Clear skies,

Watto

Offline UKJay

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Re: Amp Glow removal with Dark Frames issue
« Reply #3 on: 2017 May 23 23:44:45 »
I am having a similar issue with the same sensor on the Altair model (Hypercam 179c). I tried this last night and it did, indeed, remove the glow however it replaced it with absolute black in the same shape as the glow. This is obviously an improvement - however it wasn't what I expected (to be fair, I'm not sure what I WAS expecting!). It is easier to work with than glow but it still leaves a mismatch against the sky background and so still needs cropping. Other software packages seem to do a more precise removal (the latest Sharpcap for example).

I am therefore sure I am not quite doing it right in Pixinsight. In regards to not ticking "optimize dark frames", do I leave it unticked for both calibration of flats AND lights, or just lights? I unticked it for both.

As an alternative, could I use the master darks and flats generated by Sharpcap and just calibrate my lights from those? I know the obvious answer is to try it but, with the batch of 80x60sec subs I am working with, it takes over an hour a time to get to the end of calibrated and stacked lights so if anyone has any tips, I'd appreciate it.

I am really grateful for the OP and answer in this thread as it has moved me on in terms of dealing with my issue. Thanks.

Offline TobiasLindemann

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Re: Amp Glow removal with Dark Frames issue
« Reply #4 on: 2017 May 24 03:46:36 »
UKJay,
are you sure, that the glow is caused by the darksignal? Is the glow present at our darks too? I ask, because I wonder if it is caused by the flat. If I remember right, the sensor has an issue with too bright flats. May I ask what ADU, or % do your flats have?
Tobias

Offline UKJay

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Re: Amp Glow removal with Dark Frames issue
« Reply #5 on: 2017 May 24 05:52:45 »
I'm not at home right now so can't check however, yes, the glow is in the darks too. I can post a couple fo examples later on this evening.