Can this harm my scope?

Hello,

I wanted to shoot some darks for my CCD camera. It is currently attached to my FSQ, and it's oriented perfectly so that I can compose my target for my imaging project in the least amount of time: the CCD is rotated as it was when I first composed the image, and the focuser is extended to the focal point when I tore down.

It rarely gets cool enough in my house to get the CCD to cool to my target temperature. Tonight, I had a "brilliant" idea: put the camera next to a vent. Since I did not want to change my camera's orientation, the scope was also placed next to the vent. Sure enough, I was able to cool my camera down with cooler room to spare.

Towards the end of shooting my darks, I was seized by a sudden fear: could the temperature differential affect the optics somehow? Or am I being paranoid?

Thanks for any words, be they reassurance or caution. The scope and camera are back on a table away from the vents.
Eric

You could post this question on the Tak uncensored group but it has come up before.

I think the general idea is to not expose the lens to sudden extreme shifts of temperature. I personally doubt a cooler vent is at the order of magnitude of temperature difference that would cause optics to crack. But leaving a scope in the sun in a car in summer may not be smart or having it outside when it is really hot and then putting it in front of a vent may not be good practice.

The only data I have is if the lens is heated and put into cold water it will shatter. How hot the lens has to be and how cold the water has to be I don't know. Treat it like a fragile crystal glass cup. You wouldn't rinse that in cold water after it held hot liquid. Same deal. My opinion only.

Greg.