|6 IR LED Xbox webcam||Gardman Nest Box & webcam|
Xbox Camera Modification
First I opened the webcam (I now find this really easy - the first time was tough though), to disable the green LEDs (mainly to avoid confusing/distracting the birds), and removed the red glass filter to make it infrared sensitive.
Next, holes in the case front for the LEDs. Like last time I used a gimlet, but this time I found my smallest Jewellers' screwdriver worked quite well as a hand drill with the soft plastic.
|Holes made in case for LEDs|
This time I made six pairs of holes for 6 LEDs, but I also made the holes much nearer the lens, on the edge of the nose cone. This meant the directional LEDs will be slightly outwardly splayed, giving me broad area coverage with infrared light, rather than all the LEDs pointing the directly ahead illuminating the same area several times over. That seemed like a better idea for use in a bird box.
Next, insert the LEDs and verify the planned wiring. Then wire the LEDs together (again I just twisted them - maybe I do need a soldering iron in the house), and cover the wires with insulation tape to avoid short circuits with the PCB.
With my previous four LED in series design, the two LED power wires were close together near the USB block. This time with 6 LEDs I opted for a two parallel sets of three LEDs in series. This meant the two free power wires were on opposite sides of the PCB. Again, I positioned the circuits so the positive supply could be hooked into the red cable connection, and exposed some of the negative (ground) sheathing of the USB cable in order to connect the LED negative.
|Testing with USB 5V supply||Insulating tape, two wires free|
Finally reassemble the webcam. This took about four attempts - I did it with the webcam and LEDs powered up (using a mains charger adapter just in case it shorted out as I didn't want to damage my computer), while watching it via a second infrared sensitive webcam. I managed with small needle-nose pliers and a lot of patience - a soldering iron might be more sensible. As before, I couldn't screw the PCB down to the back of the case, but with the wires and insulating tape this doesn't matter for stability.
|6 IR LEDs active, outwardly splayed|
While that worked nicely in my initial testing, including leaving it running overnight, something overloaded it while I was working out how to mount it in the bird box. It turned out two of the LEDs had blown (one in each set of three). I'd ordered another batch of IR LEDs so I replaced them and tried again. Curiously this time the LEDs would light up and then go off in a strobe like pattern (which didn't seem to be the imaging camera over-staturating and reseting).
The LEDs were rated at 1.5 to 1.6V, so three in series should expect 4.5 to 4.8V, meaning technically 5V was a bit over the top. I was assuming once a USB extension cable was included the voltage would be a bit under 5V anyway - but I guess I was just pushing the LEDs to their limit. I spent quite a while checking all the connections before I accepted this. If I'd had one to hand, I'd have tried including a small resistor in the circuit.
Instead I went back to my original tested circuit. Four of the IR LEDs series should expect 6.0 to 6.4V, which is way above what you'd expect from the 5V rated USB supply. However, the LEDs work fine like this, but presumably just aren't operating at the maximum brightness.
While my attempt to use 6 LEDs didn't work out as planned, the decision to splay the LEDs out does seem to work very well inside a bird box. The resulting images don't have the distracting glare observed on my first attempt.
I've been round several local garden centres looking for nesting boxes - avoiding the plastic ones or novelty shaped nest boxes, or those which couldn't be opened at the roof. This didn't leave many options. I'd learnt from my first bird box camera mounting, and did a much neater jobs second time round.
|Wedge to hold base, and lip for top||Webcam sitting in cradle||With retainer and wedge|
The box used here was a Gardman Orchard Multi Nest Box, £10 from Homebase. I'm not so keen on the slate-effect roof, but it comes off with two screws which allows you to remove and change the front plate. This gives the choice of a 32mm hole (the same as my first nest box, apparently ideal for Great Tits, Sparrows and Nuthatches), 28mm hole (which I opted for this time, recommended for Blue Tits and Flycatchers), or open which suits Robins. This gives enough access and head room to mount a camera. I did have to fill in the gaps at the bottom - too much daylight was coming in and spoiling the picture.
|Middle of the night by IR only||Bright day-light from the gaps||With the holes blocked|
With the camera at the top of the box, almost touching the lid, I could get the whole floor in frame - perfect. This tall nest box seems a good match to the focal length of the provided Xbox webcam lens. The downside is the nest will be further away, and thus harder to illuminate. However, testing in complete darkness I was happy with the illumination from the 4 LED circuit.
|Nest box on wall with webcam installed|
Fingers crossed some of the local blue tits take an interest - there are quite a few in the area visiting our bird table, but perhaps they've already found nesting sites for this season. With two new webcam bird boxes up, I hope to have improved my chance of filming nesting.
Still no visitors to this box, but the little daylight getting in is causing enough of a change to the image to trigger Motion to record things with the default settings. I guess I can either do a more thorough job blocking the gaps (and avoid bird boxes with gaps like this in future) or start playing with the configuration settings.