[pmrid (Peter)]

Righto you blokes. It's raining and the forecast is for more and more and more. So I have no choice but to tinker.

That's my only excuse. That being said, here's an idea I want to throw up for your comments.

I was looking back over this thread and trying to see stuff I'd missed - brushed over - and there was one theme I kinda liked - an aluminium bar underneath the DSLR, fastened in the usual way by the screw under the camera and cooled directly from the base of the peltier.

To make matters worse, I had left my disc grinder out on the bench overnight and also had a piece of 80x200x20mm bar that was just begging me to do something.

So I cut a shape that would allow me to fasten it to the base of a TEC while maintaining electrical isolation of the top and bottom of the peltier itself. The bar then narrows to about 50mm and runs the length of the camera.

I then buried the whole assembly in some polystyrene rescued from a recent purchase of a new UPS.

In the attached images, I've positioned a heatsink and a small SLR where the proper ones would go and I've also put a thermocouple into the body of the al bar directly under the center of the camera.

Here's the plan - run the TEC and cool the bar. Because the DSLR is sitting on top of the bar and in direct contact with it, there ought to be a reasonable amount of heat transfer. Because the body of the bar is well insulated, there ought to be minimal loss of cooling that way.

As usual with such rushes of invention, I have been pulled to a halt by not having some screws the right length to attach the TEC to the bar. A trip to the hardware on Saturday will fix that and then a test of the theory.

Cheers

Peter

UPDATED:
Running it with the TEC in place but no camera yet.
Ambient 22.5. After 30 minutes, the internal temp in the cooling bar is down to 2.3C and stable. Here's a graph of the first 25 minutes.
So that's a drop of 20C in 30 minutes. How much of that would translate into the sensor I don't know of course.