Hi,

I have seen videos of quite a few planes (blu-baby also) carrying a camera onboard. They appear to either record or transmit information to a receiver. So,

1) How do they work?
2) Does a camera consume a channel from the receiver?
3) How is it connected to the battery source?
4) Any other interesting info.

Ashutosh,
There are various method of recording the subject with a plane. those method are :
Stand alone camera: like pen, USB, or mini camera which has a inbuilt battery and memory to store the video. there are various Chinese models available in local market at a price range of 2000 to 8000 with a storage capacity of 2-8gb, depends on camera quality.
Radio operated camera : : such a shark make (FPV) used by Sai, these camera are costly with more features and require a separate battery to power. the images can be recorded remotely as the images are transmitted to a ground recording equipments connected to the receiver. as far as channel is concern it is consumed only when connected to a pan and tilt system and having a free channel on your tx (separate setup). commonly available wireless setup works on 2.4 ghz technology for a longer range. the one i am talking about is also having a viewing goggle to view the exact subject live while flying.

You can try this RC Plane Camera .

http://cgi.ebay.in/RC-Plane-Kits-Helicopter-Remote-Control-Hobbies-Camera-/320643374352?pt=LH_DefaultDomain_203&hash=item4aa7d59d10

Its in my ebay shop.

http://stores.ebay.in/Shree-Gadgets