Cool Air idea....

[ZeroID]

The other night I ran the unmodified 1200D for a few hours collecting photons. Ambient temp was about 10* and by about 30 mins in the sensor was running at 24*. It finished the night at 25*. OK, not a problem, sensor is low noise anyway and the images were ok.

But I've been stripping laptops for disposal at work, heaps of them. And I have been ripping out the copper and alum heat sink assemblies along with their flat pack fans. The thought occurs that if I can port cold air into the side of the camera, I'm thinking the unused card slot, I can reduce internal heat. Filter and drying is easy enough, a TEC unit with it's copper heat exchanger will drop air temp down and a plastic pipe up to the camera from the unit mounted on the pier side should let me feed a gentle stream of clean chilled dry air through the camera. I reckon I could take at least 10* off that 25*. Just might need to drill a hole through the card slot cover for the air inlet, the first minor mod to the 1200D.

I'll build the chiller unit first and see what throughput I can acheive.

Here we go again ... :rolleyes:

[glend]

Exhaust porting is going to be important if your airflow cooling. Ducting through the slot behind the sensor might work, using the 'normal' cold finger exit on the left (assuming a 450D). I have some small scroll blower fans that I have used for PWM cooling ($4 on ebay.
Very quite, low vibration. I also have some laptop pancake fans and cold fingers that could be 'modified' to use in a dslr.
Dust will be a concern, or stopping it from getting into the sensor area. Any airflow pushed in there is going to have the ability to carry tiny specs of dust that could get on the sensor, cover glass, etc. Filtration would be required IMHO.
Why not just run an internal cold finger without a TEC? A good external heatsink/fan (and it could be small) would hold the sensor at ambient and be a very low power solution.


Will be watching your development.
Good luck.

[ZeroID]

Got heaps of various scroll fans. Filtering and cooling is not an issue. Work chucks out fine filter material all the time down to micron level for some equipment. Moisture can be controlled by a simple drying system. Air flow would be small, there are exit points at the remote/USB connector end that would be sufficient.
Trying to be a bit subtle with this, the camera is still working. :P

This is for the Canon 1200D, I don't want to open it up .... yet ...

I have thought about the simple fan\heat sink idea for the 450D. Certainly in winter it would do the job over here. Ambient at ~5*.

[astro_nutt]

Hi Brent. I've done a cooling fan job on my dslr by making a bracket which is fitted to the 1/4 mounting bolt which directs air to the underside between the lens and body of the camera. Just have to see how it works!
Cheers!

[ZeroID]

Hi AN, so the air is directed to the base of the camera?
My intention is to get it inside the camera case. Our earlier experiments with cold boxes around the cameras was that it was pretty ineffective at maintaining a low temp at the sensor. I could achieve ice formation in the case but the sensor would soon climb back up to near previous high points.
Hopefully air flowing through the camera will be more effective. The idea may end up including a cold box and recirculating the cooler air but I'll start with a free air concept first.
Let us know how yours goes.

Welcome to our little corner of wacky DIY nutters :P

[astro_nutt]

Hi Brent. Now I understand why you need cool air INTO the sensor area...Just a thought, would it be feasible to attach a vacuum line into the camera and suck cooling air through it? Thanks for the welcome!
Cheers!

[ZeroID]

Another option but it would be unfiltered and uncooled, just ambient. Plus you couldn't direct the flow where needed.The SD card slot faces at the sensor back so is a good start.

I worked in clean labs years ago and if you wanted a clean lab you pressurised it with clean air so dust could not be sucked in under doors etc. Hence the idea. Only needs a few bar of positive pressure to work.

Keep thinking ... :thumbsup:
You'll get dragged into this mess with the rest of us... :lol:

[astro_nutt]

At least I'm in like-minded company. LOL:D

[ZeroID]

For sure :thumbsup:
Keep 'em coming, that's how we solve problems and create new ideas.