[rcheshire (Rowland)]

A bit more progress. Two more images.

A trimmed 30 x 15 TEC. Removed one line of couples and resoldered the +ve wire and plugged with BluTak for testing - finished with silicon. Another option is to use two 12mm square modules (not so readily available) switching both or one for two levels of linear temperature control. I've used a $2 seconds module.

Main board fits nicely in place. TEC wires are a bit of a juggle.

Copper strip to external active heat sink.

Tested at 1.6 volts ~2amps - heat sink only - no fan. Hot side is warm to touch. Cold side bites when touched. This will improve when I get the power supplies sorted out and have a fan running.

12V SMPS will supply 12volt fan and 5A DC-DC adjustable convertor will run the TEC, at 1.5 - 2 volts and ~2 - 3 amps.

EDIT: The $5 ebay Buck convertor, adjustable voltage, will be calibrated to corresponding temperature differentials with reference to an ambient temperature of 20C (room temperature) and corrections applied for ambient temperature variations, applying ROT a table or graph. Setting temperature 2C above the camera internal dewpoint should be relatively easy - it's SMPS. Grounding the camera chassis is a prerequisite as well as good power supply filtering for reducing EMI effects. I don't think this will be too troublesome.