Improved image stability of the Philips DP75 movie projector

In 1958 Philips came with a completely new, unique projector design. The spiritual father of this construction was again the unforgettable ing. Jan Kotte. The mechanism was set up so that a complex framing device was no longer necessary. Kotte had the intermittent shaft bisected and both ends provided with hypoiet teeth.

Both ends of the shaft were linked by means of a toothed plastic bushing. By moving this bushing in the longitudinal direction of the two shaft sections, the position of the intermittent sprocket can be shifted with respect to the Maltese cross. This construction was first used in the FP20 film projector. The ends of both shaft sections were then separated by means of a steel ball. For some reasons this ball was omitted in later productions and also with the DP75, so that both shaft ends came “cold” against each sitting. This makes framing sometimes choppy. At the Dutch Eyefilm Institute we edited two shaft parts off a DP75 in that way, so again a steel ball can separates both shaft sections. Framing is very easy now and the image stability is therefore also increased.