Friday, September 07, 2007

New Peltier cooler configuration

It's done basically, except I still need some time to think of a better attachment mechanism, right now it's attached via a garment type rubber band, rather ad hoc but work, I shall use Velcro tape soon.

This time, the Peltier module is placed on the left side of the camera since I found the amplifier glow is like on the upper left, wonder if it will help or not?

The box is much smaller this time, so the dew and heat insulation should be better. And this time, a 12V power is applied on the Peltier with a larger fan, so the cooling effect should be stronger. (Remarks: after the test, I found that the unlabelled transformer which I used should be around 5V only)

I've conducted a few test, first one is 3m15s exposure each, 5 uncooled frames and then follow by 5 cooled frames, zero gain:-

Next is 10m30s exposure each, 3 cooled frames, followed by 6 uncooled frames, zero gain:-

And then 132s exposure, 633 gain, a test of shorter exposure with higher gain, 12 uncooled followed by ** cooled:-

Again 132s exposure, 1023 gain (maximum) but reduced to 903 gain after first 3 frames due to excessive noise even cooled, later reduced to 750 gain after another 3 frames, 12 cooled followed by 12 uncooled:-

Finally, 312s exposure, 612 gain 5 uncooled to 5 cooled:-

After knowing that the source was indeed 5-6V only, I searched around and found a real 12V 5A source. I plugged it in and the fan spinned really fast! And the heat sink really got very hot which should be, I know I am going to re-do everything soon.

No comments: