Time to re-consider this route, I've a Peltier module at home, and it's attached to a CPU heat sink with fan. Since the DMK is pretty small, I suppose I can simply put the Peltier module on the camera body to cool it, at least to test whether it effective or not. A cold finger to the CCD chip inside would be even better, but that would be the next step.
The major problem of cooling would be the moisture, dew will form very quickily in Hong Kong given anything below room temperature. To solve this issue, I believe that a Baader UV-IR block can help to keep moisture from going inside the camera, and the whole camera should be placed inside a small box with plenty of desiccant.
It's time to check out how much voltage I should apply to:-
1. CPU fan
2. Peltier module without overwhelming the fan
And instead of desiccant, maybe I can use heat wire to drive away the moisture first? If yes, how much voltage should I apply?
This would be an interesting project, and see if I will have time to conduct the experiments.
I've decided to make it into different phrases:
Phase 1: to use heat sink and CPU fan alone, for that matter, a CPU fan requires 12V normally, and the red pin is +12V and the black pin is 0V, and the yellow one is for sensor which is not needed for cooling a camera.
Once it's finished, I can try to proceed to phrase two.
Phase 2: peltier module is added, but this time, the hardest part is to place the whole camera into a box containing desiccant, should begin to look for a suitable box.
I've conducted some tests tonight:
1. With 9.6V DC applied to the Peltier module, it cools down very rapidly but the heat sink is also overwhelmed pretty quick, I doubt even if I turn on the fan (connection not ready), it won't be fast enough to take away the heat.
2. With 2.4V DC applied to the Peltier module, it cools down quite good, but the temperature drop is not significant, the heat sink alone is enough not to overwhelm the system, I guess higher voltage can be applied.
3. The 12V DC fan will not move a bit with 2.4V...
4. With 4.8V DC applied to the Peltier module, it cools down very nicely but the heat sink cannot sustain the heat loading, got to test if the 12V DC fan is enough to drive away the heat.
I guess I will use at least 9.6V (8 AA rechargeable) for the fan, and use around 4.8V (4 AA rechargeable) for the Peltier. Need to find a good box for the DMK.