Photo by John Kimberley, no reproduction without permission.
One aspect of telecine operation involved tariffing the film. TARIF was an acronym for Technical Apparatus for the Rectification of Indifferent Film. (There were other translations). The problem was that standard film prints have too high a contrast range and too variable a colour range to translate well into TV pictures, and so some means of correcting this was required. Where films were shot specifically for TV, special low contrast prints were used, but news items on reversal film had no opportunity to be graded other than by the camera operator getting the exposure right in the first place. The TARIF unit worked in conjunction with the TK processing chain, and was usually operated by a pair of joysticks. The left hand one affected the blacks, and had green red and blue on 3 axes at 120 degrees apart, and a twist control to alter the overall black level. The Right hand one was similar but affected the whites, with the twist control setting overall signal level (or brightness).
There was a display which showed the red green and blue signals just below the transmission monitor, to help guide the operator, and a greyscale light box above the monitor to allow for both monitor calibration and a guide to the operator for overall colour balance.
The tarif control panel also had a set of rotary switches which could be set to fix a specific colour axis and then just use a master lift and gain. This was rarely used, as it could not be changed quickly and was only really of benefit where a properly graded print had a particular colour cast which needed correcting without the need to be changed. The joystick control provided the quickest means of correcting the errors, but relied on the quick reactions of the operator.