Can I make a budget trail camera with photoelectric sensors?

Question

Only very expensive trailcams (USD 1,000+) are able to take photos of small and extremely fast stoats and weasels. So in order to monitor the presence/absence of weasel and stoat in a certain area, the Dutch working group for small Mustelids developed a combined camera-/tunnel System where cheaper trailcams (USD 300) successfully catch these small mammals.

If this monitoring system is to be used on a large scale, the price must be even lower that this. My thinking is, that in a setup as described in the combined camera/tunnel-system, a trailcam specialized in wildlife photography becomes obsolete. A cheaper camera, equipped with a photoelectric sensor and maybe an IR-flash would do the job as well.

How would such a solution look like? What camera-sensor combination can you recommend with a budget of about USD 100 – 150 for the final result?

PS: A “trailcam” in this context refers to a “camera trap” as described by wikipedia: [...] a remotely activated camera that is equipped with a motion sensor [...]. Camera trapping is a method for capturing wild animals on film when researchers are not present [...].

Answer 1

Having floated a few Raspberry Pi's down a river in paint cans during the removal of a dam, I can say that it is a decent set up, but struggles with resolving power in certain circumstances and eats power.

If it were me, I would look at building a whole integrated system. Start with a solid PVC tunnel and waterproofing for the electronics.

My personal approach to managing the imaging would be to create an ARDUINO not raspberry pi trigger system, because it will run much longer on less power is self restarting and very reliable if properly programmed.

You can use a motion sensor or an IR sensor or a pressure sensitive flex switch (which you tweak to get the distance and timing right to trigger the camera).

For the camera, I would look up affordable older models on the canon hack developer kit.

http://chdk.wikia.com/wiki/CHDK

You can buy craigslist canon cameras for $25 a piece and have immense control over them.

Google around and you can find a lot of different possible routes to a solution.

I knew of a professor who used a system like this to send up in a high altitude balloon. You would need a different trigger and different CHDK settings, but it gives you a starting place and I would say you could build everything including a tunnel for less than $125.....

Check it out here and google what other people are doing with both arduino's and CHDK.