In case of interest. With the RPi camera you have a choice: normal camera (with good color response) or Pi No-IR that can work at night with IR lights, but has poor color rendition and a bit less sharp / contrasty overall. Typical "security camera" models use an IR filter that can be physically switched out at night and in during the day, for the best of both worlds.
I was thinking about making my own IR-filter-switcher using a hobby servo, but then found another way. I used these parts:
http://www.ebay.com/itm/291404350105 "OV5647 NoIR Camera Board /w M12x0.5 mount" ($30)
http://www.ebay.com/itm/400938137287 "IR CUT M12 Mount Lens 8Mp HP Dual Filter Switcher" ($4)
http://www.m12lenses.com/8-0mm-F1-8-Meg ... 0818mp.htm "PT-0818MP 8.0mm, F1.8 Mega Pixel CCTV Board Lens" ($15)
http://www.mcmelectronics.com/product/83-16530 "Raspberry Pi 2" ($35 + shipping)
H-bridge driver for bipolar 100 mA pulse at 5 V ($?)
The ebay M12-lens-mount NoIR camera board comes with its own lens, but that one has a short "back-focus" distance so it is not compatible with the IR CUT switcher/ lens holder that slides the filter in between the lens and sensor. You need a lens with more clearance between sensor and rear element. The 8mm lens I chose from m12lenses.com works, but some others (especially wide-angle types) may not. You have to unscrew the lens mount that comes on the camera board and replace it with the IR CUT switcher mount. I've assembled this and confirmed it does work (haven't yet built the H-bridge driver for auto-switching the filter).
Just FYI, this assemble-it-yourself idea is not an amazing value. So far I have not found a M12 lens that is as good (eg resolution / contrast / distortion) as the tiny built-in lens the official RPi camera comes with, although they are usually brighter (like f/1.8 instead of f/2.9). I add up a cost of $84 including the $35 Pi without shipping or memory card (and not including the H-bridge driver) and just for comparison, you can get a working day/night IP camera board module with 1/2.5'' Aptina 9P006 5MP sensor and lens, listing for $82. http://www.securitycamera2000.com/produ ... -View.html
(but of course an IP camera still needs a separate external computer to actually record the video.)
On the plus side for the Pi approach, the camera part by itself is somewhat smaller, and with something like PiKrellCam software for motion detection and the whole Pi software & hardware environment you have much more flexibility on configuring a system.