View Single Post
Old 17-04-2021, 03:07 PM
Registered User

ChrisD is offline
Join Date: Apr 2021
Location: Melbourne
Posts: 35
Originally Posted by Tinderboxsky View Post
So, the big question: is there any advantage to be gained by spending the extra dollars on a cooled camera vs a standard un-cooled one?
I'm no expert, but this is how I look at this problem.

Reducing the temperature of the sensor will reduce the noise created in the sensor, (Dark Current) but by how much and will you see it?

Well, I've attached the Dark Current v Temperature graph for the ASI294MM pro (the MC should be the same).

The value of dark current (noise) is given in Electrons/second/pixel.
So, by the graph, at 0 degrees you will get about 0.02 e/s/p

So how does that compare to other noise sources?

Well the major source of noise in an image is sky glow.
If you go to:
you can enter you camera, scope details, and Bortle value and get the sky glow e/s/p value.

I'm Bortle 5 with a ASI294 and a C8 I get around 0.69 e/s/p from sky glow

So, for me, if the camera was at 0 degrees, I would get 0.71 e/s/p of total noise from the 2 sources (skyglow and dark current) with just 2.8% being from dark current itself.

I don't think cooling would make any difference, the noise from sky glow swamps the noise from the uncooled sensor in most cases.

You probably have better sky than Bortle 5 but you can run the figures now and make your own value judgement.

Attached Thumbnails
Click for full-size image (Dark Current.JPG)
32.9 KB17 views

Last edited by ChrisD; 17-04-2021 at 04:45 PM.
Reply With Quote