General question here … I use the cool down/warm up periods at the beginning/end of the session. Out of curiosity, what kind of time frames do you all use (if any) to safely warm up/cool down the camera? (I’m using a QSI 683.) Not sure if there are any general rules of thumb – I generally set it to about 15 minutes or so. Thx!
I’m not that conservative. I use 5 minutes to -15C.
I don’t bother with a warmup or cool down. Personally I believe if the hardware needs a warmup/cool down it should be on the hardware to throttle itself.
That’s a good point Jared. Not sure how much of it is thermal stress vs condensation risk, but good to see what others are doing.
I use about 1m per 5C I want to change because I have found in wet Florida air I get less chance of condensation on the camera cover glass. Which is something I highly like to avoid as I rarely remove the camera from the optical chain.
That’s something I never really thought about. Thanks Mick!
I’m in Jared’s camp on this one - as fast as possible. My camera has resistive film heaters attached to its front window that prevent dew, so I don’t have Mick’s concern either. With my previous camera (an ATIK 383L+) if the desiccant wasn’t fresh I would notice condensation on the CCD coverslip, so I would be quite careful about my cooling rate. I haven’t seen that yet on my current camera (an FLI PL-16803) which gets about 20ºC colder than my ATIK did. The FLI doesn’t seem to have desiccant either. It may be that the heaters on the camera window also serve to warm the air inside the camera body enough to stave off condensation on the CCD coverslip (or maybe the main chamber is just sealed better, I’m not sure).
Me too, my STT-8300 will cool to minus 30 in less than 5 minutes so I set to three. You need to wait until you see the actual temp oscillating around the set point before you can be sure it has stabilized and start images, of course, regardless of the time that has passed. This typically occurs after the cool down period has expired.