For the past month or so, I've been planning on getting an infrared camera (actually I had wanted one since the last time I had fun with IR). I managed to score a deal on a 30D and was fully set to get it converted for IR-only. The dilemma I had was deciding who to get to do the conversion. There are several companies out there offer this service, MaxMax and LifePixel to name two. My main reasons for getting dedicated IR was so that the autofocus would function and also for the faster shutter times so that I can hand-hold.
The reason autofocus gets affected is because lenses focus light at a different focal point in IR than in the visible range. Thus if you focus in the visible range, you'll be slightly front focused in IR. LifePixel claims their calibrate the camera you send them so that it focuses properly with the Canon 50mm @ f/2.8, but for other lenses you may need to stop down so that you have sufficient depth of field that your object of interest is in focus. MaxMax however claims (well it is a little vague on their site) that they can calibrate the camera such that it will autofocus properly with any lens (except the 10-22 which requires you to specially the calibrate the camera for use with that lens). I still wanted verification on this so I emailed the folks at MaxMax. While I was still thinking about this, I had the opportunity to buy a Rebel XT that had already been converted by MaxMax. Since going this route would save me a lot of money I went for it. It turns out this camera was the one Uwe Steinmueller bought and wrote about here, he eventually sold it when he got his 5D converted for IR.
I've been playing with it for the last day and so far the autofocusing hasn't disappointed (though it was off with the 85L @ f/2 but that might just have been my handholding with the narrow DOF). Even the 10-22 I have seems to focus well. There's a lot of experimentation I'd like to do, but I'm really looking forward to taking the camera to Death Valley later this year in April.
Technical Specs: Canon Rebel XT IR-only, 10-22@10mm, f/8, 1/100s, ISO 200.