Temperature fluctuation with ASI 1600mm Pro

[b36lbx]

Just wondering if this is normal or not, I recently purchased a asi 1600mm pro and while I didn’t have a chance to use it for proper imaging I though I could just build my darks and bias library. I’ve started with -20 degrees setting and noticed a temperature fluctuation of -2.5 degrees in a 2.5 session while taking darks. Can someone also let me know if I can use these files that have been shot at 17.5 degrees to combine with future lights at -20?

Many thanks

[Astrosharkey]

I have the same chip and never go below -10 degrees and find it very stable there once settled (I don't think you can massive gains below -10 but I may be wrong)

[ngwillym]

That fluctuation may have been caused by the cam having to work flat out to maintain the temp - what ambient were you working at, bearing in mind at best it can get to 35-40 below ambient?

Regards
Neil

[b36lbx]

1 hour ago, Astrosharkey said:

I have the same chip and never go below -10 degrees and find it very stable there once settled (I don't think you can massive gains below -10 but I may be wrong)

Thanks for this, I've not had a chance to do my own tests, I started from a value that was popular with other users.

22 minutes ago, ngwillym said:

That fluctuation may have been caused by the cam having to work flat out to maintain the temp - what ambient were you working at, bearing in mind at best it can get to 35-40 below ambient?

Regards
Neil

I think you are spot on, I wasn't aware of the 35-40 margin, I don't know the exact ambient temperature but I think it was close to 23-24. The temperature is supposed to drop a little in the next couple of days, I will try again then. Can you please share some tips on how to build a dark library outside imaging sessions?

[Tommohawk]

I have ASI1600 cool and work at -20. But if I try and shoot darks indoors at room temperature the cooler struggles. 

Last time I did darks was February and I had to open windows to get room temperature to about 14 Deg. 

With this fine weather I can still get to  -20 easily when doing lights; I may run into problems on a very warm summer night though. 

[Spaced Out]

Not done any darks with mine yet but I was going to put the camera in the fridge to do them. I figured it's very dark in there when the door is shut (reducing risk of any light leakage) and it's cool too.

[ngwillym]

I'm lucky in that I have a dome, so I just leave the kit capturing darks at the end of an observing session (or sometimes do it the following morning when ambient temp is low)

 

Neil

[Tommohawk]

1 hour ago, Spaced Out said:

Not done any darks with mine yet but I was going to put the camera in the fridge to do them. I figured it's very dark in there when the door is shut (reducing risk of any light leakage) and it's cool too.

Just one question... why didn't I think of that?! 

[b36lbx]

Just a quick update and to express my gratitude to everyone that contributed with comments.

I’ve done another test today, this time at -15 degrees and left the camera in the garage(a lot cooler than any room in the house) connected to a AsiAir pro so I can keep an eye on the temperature. Overall very successful the temperature stayed super steady throughout the 3.5 hours of shooting darks.

[Tommohawk]

Result!