Greg, certainly something to consider. I will start looking at mirror temps and install a sensor at the nearest opportunity. The RC has fans so it might be time to test a few ideas out too.
Brett, good idea, I forgot this was possible. Doing a check will confirm my thoughts.
The CDK has an electronic temp control but really it does not need this. Basically you turn the fans on and they are flat out all the time.Its not a problem if the mirror goes colder than ambient only if its warmer.
Now its getting warmer it does take it a good 2-3 hours to equalise though.
