Following the guide here;
I'm making a camera capable of taking near-infrared photos. The theory being that with some image processing, a photo taken with an NDVI camera can show where plants / vegetation is growing well compared to where it's not growing so well.
The hardest part involves taking a camera apart, removing the infrared filter and putting it all back together in a working state. A couple of cheapy cameras off eBay help with the practice. I destroyed the first camera but go the second going ok. Here's a photo of the camera in pieces and the image sensor.
The photos below show "normal", "near infrared" and "NDVI" versions of the same photo;