Since this summer I use an ASI6200MM Pro (mono).
The ASI6200 is powered by a dedicaced 12 Volt alimentation 3A (constant) to 5A (surcharge).
This summer, I used -15°c or -20°c cooling (75% capacity) without any problem.
About a delta t of 30°c.
This winter, here in Belgium, the temperatures are cold (3°c).
I wanted to cool the camera down to -25°c (74%). But it is impossible.
I always have Dew that forms immediately, in the center of the sensor.
When I reduce the cooling down to -15°c, the dew disappears after 10 minutes.
Then, I can use the ASI without problem with a cooling of -20°c.
If I go to -25°c, dew is back!
I tried lowering the temperature step by step, slowly. As soon as I drop below -20°c, I have a dew problem.
Is this normal, is -20°c a limit?
For info, I see a difference in quality between the images taken at -15°c and -20°c. Being able to go down to -25°c seems justified to me.
I've uploaded some sample fit images, in the file :
Here is the session :
- flat-20c-1842 : flat take @ -20°c : no problem
- flat-25c-1854 : flat take @ -25°c : dew formation
- flat-15c-1859 : 5 minutes later, Asi is @-15c : the dew is always here
- flat-15c-1906 : 7 minutes later, ASI @ -15°c : all is fine.
Thanks for your help,