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Originally Posted by peter_4059
I finally got mine all assembled today and ran some test darks with the cooler switched on and off. Here's 60 secs without the cooler (29 degC) and 60 secs with the cooler set at 17 degC. I can report the temperature held stable on the DSI readout - not even 1/2 deg swing.
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Looks great Peter!
I think the onboard CCD temp in Envisage is pretty slow to respond. It certainly takes a while to show change when I turn on the peltier.
Quote:
Originally Posted by peter_4059
I also installed my desicant holder and this seemed to work ok (no free water droplets inside the camera when I opened it up).
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Sounds promising!
I'm leaning towards filling up the volume around the finger as the way to minimise condensation.
I figure that I just can't risk any moisture sloshing around in the camera so I tried another concept today.
I heated up the cold finger with a heatgun and pressed it into some polystyrene foam so it burned it's way down into it.
After some experiment I got the temp just right so that it wouldn't burn cavities away and have air pockets around the finger.
With some downward pressure on it as it melted into the foam I then poured cold water over the faceplate to quickly cool it and stop the melt.
A few tests with this and it held the same 2°C delta at a setpoint of 3°C. With the insulated shroud it also showed some thermal inertia as well. When the peltier cut out it continued to cool a few tenths of a degree before starting to warm up.
I then cranked it to see how low I could get it to go.
Ambient roughly 21°C...finger got to -5°C easily. A differential of roughly 26°C.
So , theoretically, I should get to below 10°C on a summer night of 35°C
Steve