Any fix for amp glow ASI183MC

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johnc3457
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Joined: Tue Jun 19, 2018 5:41 pm

Any fix for amp glow ASI183MC

Post by johnc3457 » Tue Jun 19, 2018 10:08 pm

Still dealing with the amp glow problem is there any work around, subtracting dark frames does clean it up some but still leaves some problemsImage

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Sean.Wang
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Re: Any fix for amp glow ASI183MC

Post by Sean.Wang » Wed Jun 20, 2018 6:47 am

Hi, there.
Are you use a uncooled version?
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johnc3457
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Re: Any fix for amp glow ASI183MC

Post by johnc3457 » Sun Jul 22, 2018 6:01 pm

The camera is cooled and I still get the amp glow on the right side all read noise is usually taken care of by the cooling but amp glow is still present

johnc3457
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Re: Any fix for amp glow ASI183MC

Post by johnc3457 » Sun Jul 22, 2018 7:38 pm

ampglow frame 3.jpg
Attached file is cooled to -40 this reduced the normal noise but the amp glow at the right is very hard to remove even with dark frames. This was a 300 second exposure of M51 un stretched and with no preprocessing.

davebl
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Re: Any fix for amp glow ASI183MC

Post by davebl » Sun Jul 22, 2018 9:41 pm

M8_120S_Sm2.jpg
I have the Mono version of this camera and I found that lowering the gain and using shorter exposures seem to help. I'm still experimenting, but my skies are filled with smoke right now, so I'm on hold. I'm attaching a 120 second exposure in H Alpha, single frame with dark subtracted. Cooling to -20c.
Dave

davebl
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Re: Any fix for amp glow ASI183MC

Post by davebl » Sun Jul 22, 2018 9:44 pm

Here's the same image without the dark subtracted. It seems that the darks don't do a lot to hide the amp glow. My gain is set to 0.
Dave
Attachments
_H_Alpha_1x1_120.000secs_M 8_00000534.jpg

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Sean.Wang
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Re: Any fix for amp glow ASI183MC

Post by Sean.Wang » Tue Jul 24, 2018 6:07 am

Hi
I think it is a inperfect calibration.
Dark frames maybe need to take again. with same exposure, gain, offset and temperature as light frames.
You can directly use master dark to calibrate light frame, without bias this time.
ZWO | Marketing Consultant
Location:lon=120.6 lat=31.3
SuZhou China

motto:
Don't face one's fate, can't be a real man;
Don't know manners, can't be gentle;
Don't know meaning behind the words, can't understand man's heart.

Konihlav
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Re: Any fix for amp glow ASI183MC

Post by Konihlav » Thu Jul 26, 2018 7:17 am

for amp-glow tests (calibration tests) you may check my experience where I describe how to quickly check if calibration works (on CMOS cameras)
http://blog.astrofotky.cz/pavelpech/?p=1442
BTW with CMOSes there will always be a very, very little leftovers. Maybe only if you take the individual darks the same night (when camera was turned on) it might be 100% to calibrate out (so far I can reach some 99% which is OK for me).
Also, you have to use moderate gain, not completely zero and not too high.

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Sean.Wang
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Re: Any fix for amp glow ASI183MC

Post by Sean.Wang » Thu Jul 26, 2018 1:03 pm

Konihlav wrote:for amp-glow tests (calibration tests) you may check my experience where I describe how to quickly check if calibration works (on CMOS cameras)
http://blog.astrofotky.cz/pavelpech/?p=1442
BTW with CMOSes there will always be a very, very little leftovers. Maybe only if you take the individual darks the same night (when camera was turned on) it might be 100% to calibrate out (so far I can reach some 99% which is OK for me).
Also, you have to use moderate gain, not completely zero and not too high.
Thank you so much for share your experience, it's a good for all of our users.
ZWO | Marketing Consultant
Location:lon=120.6 lat=31.3
SuZhou China

motto:
Don't face one's fate, can't be a real man;
Don't know manners, can't be gentle;
Don't know meaning behind the words, can't understand man's heart.

johnc3457
Posts: 4
Joined: Tue Jun 19, 2018 5:41 pm

Re: Any fix for amp glow ASI183MC

Post by johnc3457 » Tue Aug 07, 2018 5:02 pm

Working on the calibration has helped a lot also limiting exposures to 120 seconds. Attached file is of M8 taken from high light pollution skies in downtown El Paso TX, I'm not sure what Bayer pattern is in use but with my old camera all of the Ha areas of the nebula were red, is the chip setup for RGGB or BGGR?

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