Quote:
Originally Posted by Peter Ward
Just like a cold can of XXXX on a warm summer's day, too high a delta-T will always cause condensation (and eventually icing).
Pro cameras, such as SBIG, have sealed chambers with desiccating plugs, plus the chamber window is heated.
Further, the CCD chamber temperature is stabilised to 1/100th of a degree to allow accurate dark frame calibration.
Sure, lowering the camera temperature helps....but there are limits on unsealed systems.
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Ooops, didn't see this first.
Thanks Peter. I think I can duplicate the sealed chamber and plug idea. I have enough hardware, now all I need is a 1.25" clear glass filter for the front window.
Heating... maybe airflow or maybe a resistive collar.
Here's a pic of the proposed setup. It's an unusual 2" adapter I acquired somewhere with a tapered collar, thus reduced contact surface. Insulators will go on the flat surface and I could wrap a resistive heater around the barrel and filter assembly (Couple of 1.25" EP extenders with a temporary yellow filter on front) that protudes forward of it into the focusser tube.
Or the warm air idea of course.
I may drill and tap another hole into the side of the adapter opposite the lock screw for a silica plug to screw into.
(Can you tell I'm having a quiet day at work ...
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