Saturday 24 March 2012

Xbox Birdbox Mk III

Yes, I made a third bird box with an infrared modified Xbox Live Vision webcam. This used 4 IR LEDs as in my original design, but splayed even more than in my second attempt.
4 IR LEDs on webcamCrude wooden clampsWebcam installed in birdbox

The left/right sloping roof of this nest box means this time my camera is off centre, nestled up as high as it can go so as to maximise the field of view. The bits of wood in the photos hold the base very securely, but the camera can still rotate, so I have attempted to pin it with a couple of nails - hopefully that will do the trick. Like this it can cover almost the whole floor, and with the LEDs splayed out to give indirect illumination, there are no obvious 'white out' bright spots on the image (and before):
Look what was inside the box!The empty bird box floor (by IR)
This nest box was from a local independent garden centre, and I got a discount to £5 as it was 'ex display'. I guess it had been outside for a while as when I opened it to test the camera I found a small old wasps' nest inside.
Birdbox installed, note USB cable in protective bag
This time having run out of obvious spots on the house in easy range of a suitable vent/window, I decided to mount this bird box on a tree down the garden. The site seems promising, as in the first couple of days I caught sight of a tit going inside to have a look.

USB Extensions
While I hope the bird like the new bird box's location, it is well beyond the USB specification's 5m cable limit - so how will I connect a computer to the camera for automated surveillance?

I'm already using a normal passive 2m USB extension cable on the second bird box camera. That seems to work fine, as you would hope given the Xbox Live Vision webcam's own USB cable is 2.75m (9 foot), making in total almost 5m. Trying a normal 5m USB extension cable bringing the total length to 7.75m didn't work (although it did with another webcam with a shorter cable).

I have bought a 5m active USB repeater cable, and tested that inside the house. This was via eBay, offered by multiple sellers. The build quality isn't great (the female USB socket is loose), but it does seem to work. However, the frame rate at VGA resolution was noticeable reduced - sometimes taking seconds to update. This does not bode well for an even longer cable or if daisy chaining these USB extenders.

I also bought a USB over ethernet (aka CAT5/CAT6 RJ45 Lan) adapter on eBay, which in theory can be used with a network cable of up to 50m. Perhaps this was a dud - I tried a couple of network cables and different model webcams and it didn't work at all.

An alternative idea is to put a computer out in the garden near the bird box - a shed would be ideal but we don't have one. I suppose I could build a waterproof box for the laptop like these guys did (with an Arduino and DS1621 temperature chip for monitoring as well as a birdbox webcam).

I'm thinking about a mini-computer like the new Raspberry Pi, but that's currently not yet available. It would only need a modest power supply, so I might be able to handle that via power-over-ethernet (POE), meaning I'd just need to run a long ethernet cable to the end of the garden. Something to think about... see also this thread on using a Raspberry Pi for CCTV. Update - and see this post, where I've started trying out a Raspberry Pi for this task, and this post for how to power it.

For the moment, I will just have to take my laptop down the garden periodically if I want to check the camera.

Update - Watching the box
At the weekend I decided to move the box higher up the tree, to about 2.5m off the ground. This was for two reasons - first I'd seen a cat in the garden (quite unusual) so wanted the box a bit more secure. The second reason was to make it easier to watch from the house.

After a little spring pruning, I now have a direct line of sight and was able to try my telescope on it. The target is about 25m away from the house, and with the 25mm wide angle eyepiece I got a pretty nice view of the front of the birdbox. However, this was with the focus at maximum and the eyepiece lifted up slightly and held on the thumb screws - maybe I should get a 1.25" extension tube? Reaching focus wasn't a problem with the web camera attached to the telescope though.

Is anybody watching?In she goes!Peeping tit

I caught a few nice shots and a short movie by watching patiently - and then switched to letting the computer do it for me with the Motion software, in addition to recording any action from birdbox one or birdbox two. That got quite a few more good shots that afternoon, with multiple inspections by blue tits, and possible two of them in the box at once. The frame rate with this triple webcam setup isn't great so it is hard to be sure. This is only a short term solution to watching the nest box - after all, I do still intend to look at the sky with the telescope given half a chance!

Update (4 June 2012)

I gave up with the telescope + webcam for watching the birds box during May - the trees along the line of sight are now all in leaf, and with any wind triggers false positives meaning loads of unwanted images got recorded. I'm toying with getting a second hand spotting scope to use with the webcam instead - ideally something weather proof.

I've also tried out another 5m USB repeater extension cables which didn't work for me, and an alternative USB-over-ethernet kit, with limited success. Like others before me (based on internet browsing), I've come to the conclusion that USB extension is not a good plan for webcams. It looks like plain old ethernet is indeed the way to go, which requires an IP capable webcam I can squeeze in a bird box, or a computer that can live in the garden.

I'm still waiting for my Raspberry Pi, but other people have already got their Raspberry Pi hooked up to a webcam and running motion. The hardware connectivity possibilities for coupling sensors are exciting too (perhaps an IR beam over the entrance to automatically count visits and trigger the webcam?), and also controlling hardware - for instance internal lighting. One guy is even trying to do a bird feeder sensor linked to a 'real' camera's trigger.

Update (2 August 2012)

My Raspberry Pi has arrived, and after a delay sorting out a working SD card, I've started trying out webcams with a Raspberry Pi.

Update (29 September 2012)

I've added a couple of photos testing this nest box camera with a Raspberry Pi using passive power-over-internet, working at up to 30m.

Update (2 October 2012)

Powering the Raspberry Pi with 24V passive POE works at 40m (indoor testing). Outdoor testing to follow...

Update (January-May 2013)

The Rasberry Pi has been installed in the garden primarily to monitor this bird box. It survived some unexpected snow, and this spring Blue Tits have laid a clutch of seven eggs.

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