I've been using FTNoIR for a while now. At first I was using only face tracking with webcam app on my smartphone. I was blown away at the accuracy. Occasionally it would lose track, setup was a hassle and having a beard or any facial hair ruins the face detection. So, I went out and bought a PS3 Eye Toy. Using face-tracking the PS3 camera was actually worse than the smartphone webcam app. I decided to give IR a shot and Macgyver my own 3-point IR tracker for less than 10 dollars in parts from radio shack. Even with 940nm IR LED's the tracking was basically impossible due to the IR filter in the PS3 camera. (at least on my version)
Moving forward, I decided to remove the IR filter from the camera. After a frustrating few hours I had the filter removed and had the camera reassembled. Not a single spec of dirt on the imager! I picked up my IR tracker, aimed it at the camera and... the image looked like a glaucoma patient's vision. It was extremely washed out, distorted, and totally useless for tracking anything.
Upon further inspection I realized the focal point of the camera had shifted, by a huge amount. The image would focus crystal clear, only approximately 3 inches from the lens. Googling turned up some pretty insane countermeasures and most insisted it was a lost cause. After deep meditation, I realized that the removal of the IR filter had upset the focal length and the solution was simple. Either move the lense assembly forward or backward from the imager. Reluctantly, I disassembled the camera again but left it plugged into the computer. I tried shimming the lense slightly outward and realized the focal point was only getting closer. So, I grabbed a piece of 800 grit sand paper and very, very cautiously sanded the base of the lense housing, frequently checking the focal point. It didn't require much sanding at all and voila! It was fixed, objects on the other side of my room were in focus. Now I could finally try my IR tracker that had been collecting dust.
Honestly, there is no comparison. Point tracking is incredible. Face Tracking is very impressive and will preview the feeling of immersion and added SA. Unfortunately, without stereoscopic cameras, face-tracking can't hold a match to IR point tracking. It is extremely intuitive, you look in the direction you want and thats it. It's like trying to convince someone in the not too distant past why they need the internet or a smartphone. Until you try it, you'll never understand.