Each frame is divided into 2 fields. The first field (lower field) is scanned as Digital Scan. The second field (upper) – Digital Video (D.V).
25 F.P.S. = 50 fields per second.
Frequency is measured in Hertz (Hz). Cameras record in 50 Hz (or 50i) (interlaced). Both of the fields are scanned at the same time.
Bars and tone – 1 KHz. Bars are the colour the camera sees (red, green and blue). White balance helps you to get the right colours when filming and the indoor lighting is called Tungsten which helps correct the colour. Camera T & W is what you press when you zoom in or out, it is called tight and wide. Cameras film in Red, Green and Blue colours. We learn about this to avoid distortion when we’re filming.
1Khz is equivalent to 4 p.p.m (Peak Programme Metre) and -18dBVU (decibels and virtually useless)