Cooled Camera (ZWO 183GT) Target Temperature

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schmaks avatar
What should my target temp be with my cooled camera?
Chris White- Overcast Observatory avatar
The benefits of cooling to below 0 degrees are incremental so at least to 0 degrees.  I like to cool so that I'm only needing about 50% of TEC power to achieve my target temperature.  I'm in the NE USA, so that means in summer I cool to -5C and in winter I cool to -25C.
schmaks avatar
Thanks. Sorry but what is TEC?
Chris White- Overcast Observatory avatar
Thanks. Sorry but what is TEC?



thats your camera cooler. The power percentage is reported by your capture program.
Chris White- Overcast Observatory avatar
Thanks. Sorry but what is TEC?



TEC is ThermoElectric Cooler
Andy Wray avatar
I keep it simple … I cool to -10 degrees all year round so that my darks are consistent.  It depends where you live, but where I am the camera can usually get to that temperature regardless.  I think you'll find most people do this.

You would get a very marginal improvement on noise by going lower, but you'd wait ages for it to get there.  Also, during summer months it would never acheive that so you would end up having to take separate darks at different times of the year. 

Hence why I say keep it simple … -10 degrees all year round smile
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schmaks avatar
I’ve been shooting at 0. Assuming to switch, I have to reshoot all darks, flats, etc?
Chris White- Overcast Observatory avatar
Andy Wray:
I keep it simple ... I cool to -10 degrees all year round so that my darks are consistent.  It depends where you live, but where I am the camera can usually get to that temperature regardless.  I think you'll find most people do this.

You would get a very marginal improvement on noise by going lower, but you'd wait ages for it to get there.  Also, during summer months it would never acheive that so you would end up having to take separate darks at different times of the year.  Hence why I say keep it simple ... -10 degrees all year round



Hah!  Where I am I have had more than a few nights where ambient was lower than -25c!  On those nights I cooled to -35 or-40 just to have a consistent temp.  Cooler was at like 10%
Andy Wray avatar
Hah!  Where I am I have had more than a few nights where ambient was lower than -25c!  On those nights I cooled to -35 or-40 just to have a consistent temp.  Cooler was at like 10%


Wow!  That is pretty cold.  I will correct myself by saying again that it depends where you live, however I would suggest aiming for a consistent target temperature all year round (if you can) so that you don't need to keep re-doing darks.  In Northern and Central Europe that would normally mean setting it to -10 degrees C.
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Tom Boyd avatar
Andy Wray:
I keep it simple ... I cool to -10 degrees all year round so that my darks are consistent.  It depends where you live, but where I am the camera can usually get to that temperature regardless.  I think you'll find most people do this.

You would get a very marginal improvement on noise by going lower, but you'd wait ages for it to get there.  Also, during summer months it would never acheive that so you would end up having to take separate darks at different times of the year. 

Hence why I say keep it simple ... -10 degrees all year round

This is exactly what I do...
Arun H avatar
Like Chris, I live in an area which gets colder than -25C on occasion, and those are the nights that tend to be clear.

I have a family of darks at different temps: -10 C for most of the year, and -25 C for winter. 



To answer the question asked about darks at 0 C, yes, if you change the temperature, you will have to redo your darks.  If your flats are calibrated, simply changing temperature isn't a reason to retake them. However, I find flats last much less time than darks do, because dust on filter moves, long term repeatability of filter wheel position, etc.
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matthew.maclean avatar
@schmaks 
the only other constraint is that, if the camera is cooled too much in high temperature and humidity, sometimes condensation can start to form on the camera window. Most of the newer cameras have small heaters in the window frame to help prevent this. It may heat the window automatically, or it may be an option you have to turn on in the software settings depending on the brand/model.

It will be obvious if it does happen to you. I only saw it once in mid-summer with a temperature about 25C and near 100% humidity. My initial TEC temperature of -10C was too low, and I had to bring it up to 0C to prevent fogging. As others have said here, you may find that it works best to have different summer and winter settings.
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Michael Finan avatar
I re-shoot Flats every trip. I'm also breaking down and setting up again. Dust, etc moves every time. I also shoot at -10 C every night. In Central FL, it can be tough to get to -10C in the summer. FWIW, there aren't many clear nights in FL in summer, so on the lucky weekend I'll just shoot new darks at 0C.
Nathalie Lelie avatar
I live in Fort Lauderdale and wasn't sure I could have a cool camera in Florida.
Tony Gondola avatar
Oklahoma summer nights are hot so I'm using -5 with my 585pro, even that can take over 70% power on a lot of nights here. Once it cools off later in the year I'll bring it to -10. I don't think there's much benefit to going lower.
Nathalie Lelie avatar
Oklahoma summer nights are hot so I'm using -5 with my 585pro, even that can take over 70% power on a lot of nights here. Once it cools off later in the year I'll bring it to -10. I don't think there's much benefit to going lower.

Thank you for the info.