Cooling camera during sensor analysis

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je2000
Posts: 10
Joined: Wed Sep 08, 2021 2:46 pm

Cooling camera during sensor analysis

#1

Post by je2000 »

Should we be cooling our CMOS cameras for this to match anticipated temps or does it not matter for the analysis? Also should this be done for every filter? I am in the middle of running an analysis using my Ha filter.
nexusjeep
Posts: 293
Joined: Thu Oct 18, 2018 3:01 pm
Location: Gloucestershire

Re: Cooling camera during sensor analysis

#2

Post by nexusjeep »

Hi
My understanding is the camera should be cooled to the temperature that is used when capturing as it is mapping the noise characteristic as part of the process it is also analysing the actual cell characteristics so is filter independent. I usually do it without any filter and just use the light from my flat panel but a light wall and a lamp can work just as well. You would only need the filter in place after the cell has been analysed if measuring the background light pollution for use with the brain function to work out the optimal exposure to get above the noise threshold of the sensor when imaging.

Cheers
Nick
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admin
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Re: Cooling camera during sensor analysis

#3

Post by admin »

Hi,

cooling is not essential while running the analysis - typically the analysis completes without needing to go above 1-2s exposures, which means that the effect of temperature on the results is very very small.

You also don't need to worry about filters when running the analysis - your are measuring the characteristics of the sensor chip, not the filter. You *can* use a filter if it helps get the right brightness for the analysis to run, but no need to, and certainly no need for a separate analysis with each filter.

cheers,

Robin
je2000
Posts: 10
Joined: Wed Sep 08, 2021 2:46 pm

Re: Cooling camera during sensor analysis

#4

Post by je2000 »

Great, thanks! I am a beginner and working on some shots I took in Pixinsight. They are H-alpha narrowband subs at 90sec with a low gain of 70. Brightness was pretty low too. This is with ASI1600. The filters are 5nm Astrodons. I am getting some gradient and when I really think about it and look at the target in Stellarium, it's highly possible the gradients are coming from the moon and a neighbors porch light. I thought the filters should eliminate this but maybe not completely at 3 hours total integration.

I ran the test at -5C but plan to image at -15C. I'm guessing the suggestions won't be that far off from one another. Any idea which way to sort of manually offset the suggestions?

I am pretty thrilled with how it's looking so far anyway. I may try again tonight and see what The Brain says and just run with it and not be so afraid of Gain on the ASI1600MM-C Pro.
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