cctv cable connection

[sniper]

Could anybody tell me if it is possible to connect a cctv camera using 6 core cable using two of the wires to carry 12v power supply?
What would you do with the other wires and how would you connect them to a bnc connector (or is there a different kind of connector)? The fitting on the camera takes a bnc connector.
Is there a maxium distance you can run a cable for power (12v) and for picture.

[Admin]

12 Volts should not be run over distences greater than 100m. Always measure the voltage at the far end to ensure there is no major drop off. If the 6 core is just for power I would treble up the connections to ensure better travel of the DC currant.
If you want to send video down cable then Cat 5 is required with balum converters (http://datainterfaces.com/Balun-B1S-single_BNC.aspx) .
For greater distence these can be powered converters