In reply to bencollins:
> (In reply to MaxWilliam) Thanks for an alternative viewpoint. This bullet cam + video recorder was the route I initially was thinking of but couldn't find video cams that had "AV inputs". Which particular model of Canon video camera do you have? Do you carry several bullet cam lenses and interchange then? How durable/weather resistant do you find such a system?
I use pretty much the exact same setup as MaxWilliam.
A few things to consider.
1) Camcorder: The cheaper end of the MiniDV camcorders tend not to have AV in. Mine (I forget the model and can't check as i'm in work) is a Sony and was around the £700 mark (About 4 years ago). I understand that the reason the cheaper ones don't have the AV input enabled is to do with licencing issues regarding the algorithms used. A bit like Codecs on a pc. The manufacturer have to pay x amount for the DV output software, and y amount extra if they want to DV input software built into the camrea. I believe (but have no first hand experience) that many cameras without AV input enabled can be 'chipped/hacked' to enable it. pehaps have a hunt round google to see what you come up with. the cameras use the exact same plug and socket for AV input and AV output so don't worry if you can't see a physical AV input socket.
2) For almost all my shooting with the helmet cam i use a 2.9mm lens. I don't have much footage shot using in online but there is a low resoultion video shot using it that i put on youtube here:
http://www.youtube.com/user/jaswauk#play/uploads/5/YY6sTAKxiGk 3) The head cam Maxwilliam mentioned is fine outdoors. It actually warms up in use which stops condensation forming on the lens and is fitted with rubber seals etc. I've used it in pouring rain and is snow - no problems at all. The reset of the gear, the Camcorder and batterypack, I keep in a plastic lunch box - I cut a small nick in the top corner of the box so that when the lid is fitted there is a small hole left for the cables to come out. This makes it fairly rain proof and gives the gear some physical protection from knocks and bangs. This then goes in my backpack, rucksack etc depending what i'm doing. If it a nice sunny day then rather than going in a back pack i have operating with battery pack in one pocket and camera in the opposite pocket. you'll want/need an external microphone (the kit max linked to includes one i think). If i'm wearing a helmet i normally mount the mic inside it which keeps it out of the direct wind but makes it pick up your voice nicely. The cable routes up with the cable from the camera - a few wraps of black tape nake it all 'as one'.
4) Mounting wise, if i'm on my bike it gets cable tied to the vents on the top centre of my helmet (as per youtube video). my helmets profile lends itself to this nicely. For skiing i have drilled a small hole in the ear muff part of the helmet (doesn't form part of the actual helmet shell itself) and attached a 22mm plastic pipe clip. The camera is just a bit too thin to grip this firmly but i've got a couple of mm of black tape wound round the body that makes it fit nicely. For climbing I have an old climbing helmet that I drilled a 3mm hole in and fitted a 22mm pipe clip with small nut and bolt. Not ideal drilling a hole in climbing helmet as it will greatly weaken it. But better than no helmet at all - make your own choice on this one.
I've even had it taped to the side arm of a pair of oakleys before now.
Battery life. Probably the coldest extended conditions i've used mine in has been during skiing trips. I can happily take it out and use it all day. My lanc remote is slightly different to the one max mentioned. It has a physical toggle switch rather than push buttons. One flick of the switch makes the cam-corder turn itself on, and start recording from external video source, flick the switch the other way it stops the camera and turns it off again. The time between flicking that switch and actual recording starting is less than about a second. I replaced the switch with a double pole unit, using the second pole to switch the power on and off to the camera and microphone from their own battery. You could just as easily use a totally seperate switch to do this job or just leave the camera and microphone turned on all the time. With the camera and microphone turned on all the time, using a battery pack with 5x AA size rechargable battries you will get about 4 hours use in very cold temperatures. Probably a more like 6 or 7 hours in more 'normal' temps.
The way I am set up With a full camcorder charge and a full battery pack charge for the head cam/mic I can easily fill three to four 60 min DV tapes over the course of a 12 hour day - thats with switching the power on and off to the camera as mentioned.
Hope this is of some use!