ok, so im using cat 5 for some of my longer runs, is ther any chance that i can use the same cat 5 cable for both camera feed and power?

It would depend on the type of wire (gauge, solid core, stranded), camera power type (AC or DC), voltage (12 or 24v) power draw of the camera, and the length of the run, as these would decide how much voltage drop you would get in the cable.

It depends on the current drawn, as the higher the current, the greater the voltage drop..

220v should not be used in cat5, it should be ran in seperate mains rated cabling, and it should not run close to (parallel) with video.

Local safety/wiring codes will need to be adhered to also, for safety and insurance purposes..

for gauge 24. how long can you run 12V power? also, running 220V can it interfere with the video signal?

sir do you have a formula how to compute it? so i can decide whether to add additional pair to the power.