Cooling Question

davebl

So when I set my camera to cool at -25c and the current temp is +20c, the camera starts cooling from +20c down to -25c. My question is am I cooling the camera by 25c or 45c?

Thanks,

Dave

darkmatter

You're cooling the camera by 45C. +20 to zero is a 20 degree difference, and zero to -25C is an additional 25 degree difference so 20+ 25 = 45C.

Jarno

davebl

Thanks Jarno.

I always assumed the setting was for below ambient, but the other night I thought about it and realized I might be cooling more than I thought and stressing my cameras cooling system. It seems so obvious when you think about it. I'll have to start setting my camera temp according to the current temp each night. Sometimes the easy stuff is hard to see.

Dave

applal

I too, was unclear about this, as to whether the setting was relative or absolute. Knowing this helps a lot!

Thank you!

Support@ZWO

You can see the FAQ on our website:https://astronomy-imaging-camera.com/faq

applal

The FAQ indicates cooling is relative to ambient.
this is virtually useless.
I and every serious astrophotographer out there needs absolute settings, not relative.
The FAQ is dated from 2018. Is it still correct?

blue

The cooler temperature you set in whatever imaging software you are using is an absolute temperature, cooling to -10 is cooling to -10.

The cooling CAPABILITY (Which is what the FAQ is talking about) is relative to ambient. I.E. if the cooling capability is 40 degrees delta and the ambient temperature is 30 degrees, you will not be able to cool the camera to -20, -10 would be the lowest temperature you could achieve and even that would be a bit doubtful, it might get there but the heat sink will end up saturated and you may not be able to maintain it. I have encountered that with my ASI294 where on very hot nights it maxed out the cooling and the entire camera body ended up warm as the heat sink could not reject enough heat to manage the requested sensor temp. The only options there were to wait for ambient temp to fall or set a warmer sensor temp that it could maintain.

I cool my ASI2600 to -10 as it performs very nicely at that temperature and can maintain it year round with the exception of maybe a very few extremely hot nights, so I can re use my dark frame library until the sensor ages enough to need new darks.