Glutton for punishment that I am, I've started another diploma - Advanced digital photography. One of the genre, we're studying is infra-red. I have bought an infra-red filter to try out. The lesson I've learned today, is don't try on a windy day. The shutter speed is so long that trees become blurry. I haven't been able to get the bizarre typical infra red colours, I think you might need to get a camera converted for that, but it's an interesting experiment