Museum of the Broadcast Television Camera

Marconi MkVIII Television Camera Varotal 30 lens shot box

Marconi MkVIII Television Camera Varotal 30 lens mounting

A = Two speed gearbox for focus drive.
B = Focus control handel attachment spigot.

C = Lens focus drive shaft.
D = This shutter has the diascope mirror on the inside. Some cameras have an additional shutter that covers the aperture and disengages when the lens is fitted.
E = This safety catch prevents the lens falling forwards and has to be held back when removing the lens.
F = This screw engages with the lens to secure in in place. When correctly tightened the lens back focus should be correct.


The only back focus adjustment is by moving each tube and when correctly set should be the same for all early lenses. Some later lenses do have a back focus adjustment.