Request that ambient temperature be used as camera warmup parameter

From @kookoo

I use an Atik 383L+ and when i end my imaging i want the warm up procedure to warm the camera until it hits 0% power consumption and then turn off (i come from maxim DL and it is a very useful feature). Right now the only way to warm up the camera is by knowing the ambient temperature of my imaging site by using a USB thermometer and warming up my camera to 3-5 below ambient. This method can cause errors especially for those that don’t use external thermometer to measure ambient temperature and warm up their cameras above ambient temperature.

I have always wondered why it is useful to gradually warm up by ramping down the cooler power. Does it extend the camera life? Result in some other benefit as opposed to just turning off the cooler? In 20 years I have never seen anything significant happen from just turning the cooler off although I do generally use the “warm up”. This is with both (formerly) MaxIm and now in SGP.

I don’t know. Ask some folks and they will lecture you about thermal stress dynamics on electronics. Ask others and they will tell you that, while this is true, the thermal tolerance to this stress is longer than the electrical life (or useful life) of the CCD.

This is personal taste and a question best asked of your camera manufacturer.

For the electronics there isn’t much difference whether you turn off the cooller or warm it up. But the other mechanical parts such as the internal glass the protects the sensor this procedure is important. The first year i had my camera, and during the summer at one session the power jack to my camera disconnected while it was at -10C, ambient temperature near 15C, and i didn’t notice. The result was a cracked glass due to thermal shock and i had to send the camera back to the factory.

A clarification to the request is that the warm up procedure should gradually warm up the camera to a power consumption of 0% and then turn off the cooler. This is independent from temperature settings that might confuse the user or force them to use a thermometer to measure the ambient temperature in order to warm up their camera at different ambient temperatures at different days. A side note is that this option will warm up the camera at a temperature near the ambient temperature.

The Atik camera driver does the Atik defined warm up procedure when cooling is turned off by setting the ASCOM driver camera.CoolerOn property to false.

That seems to do exactly what you are asking for. I expect that SGP implements this.