Fisheries Extension Education (2+1)

Cameras

This has optical and electrical component which are the picture tube and lens. The surface of the picture tube is highly sensitive to light, when the light hits the picture tube surface it is converted into an electronic signal called a “video signal”.

To create the video signals the picture tube scans or draws the picture is thus received as a kind of line drawing. A electronic gun at the one end of the tube shoots a charged particles at the photo sensitive surface to the tube. Then it scans 312.5 lines called one field and fills in the spaces on 625 line standard. Two complete fields make a frame. The image formed in the camera tube is electronically transmitted through a cable to the video recorder.