Sorry stuck atm talking to a man about a PSU. My DIY is not working I need a new PSU now. Hopefully soon within a few days.
I tested the TES2-19003 @12V DC....managed down to -22ºC in 10 mins (was -17ºC in 5 mins, ambient 20ºC) @2.2A, a delta of 42ºC!
That said we need something constant not something minimum. However I get the impression this TEC would easily run at -15ºC ~-18ºC in camera but I need to try different try different combinations of power first.
My new thermoelectric controller display changes from points of a ºC to whole ºC when it reaches -10ºC. Limited digits....bummer!