Altered negative-feedback diaphragm control during implementatio

Details Altered negative-feedback diaphragm control during implementatio Altered negative-feedback diaphragm control during implementatio

1978-05-10

1979-05-08

Adams, Russell E.

Optics: motion pictures

Special effects

Transition effects

352141, G03B 2136

Patent

active

041533526

ABSTRACT:
Normally, the negative-feedback diaphragm control system of the motion-picture camera works off a through-the-lens photosensitive element. However, when an image fadeover is to be effected, the lower than normal-operation aperture size commanded for the diaphragm results in a decrease in the light incident on the through-the-lens photosensitive element creating problems if the diaphragm control system is to continue to respond to scene-light changes during the lower than normal-operation aperture-size situation. Accordingly, the through-the-lens photosensitive element is switched out of the control system, and a second photosensitive element is switched in. The second photosensitive element does not operate through-the-lens, but instead is positioned behind an auxiliary light attenuator the front of which is exposed to ambient scene light. The auxiliary light attenuator is coupled to the diaphragm and diaphragm-adjusting motor. When the second photosensitive element is switched in, also switched in is a corrective unit which redefines what the equilibrium state of the negative-feedback diaphragm control system is to be, to take into account the difference in light incident upon the second as opposed to the first photosensitive element.

REFERENCES:
patent: 4003646 (1977-01-01), Freudenschuss et al.
patent: 4106864 (1978-08-01), Burgermann
patent: 4106865 (1978-08-01), Burgermann
patent: 4116552 (1978-09-01), Wagensonner
patent: 4118714 (1978-10-01), Okajima et al.

Affiliated with

Also associated with

Rating

Altered negative-feedback diaphragm control during implementatio does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Altered negative-feedback diaphragm control during implementatio, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Altered negative-feedback diaphragm control during implementatio will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1231294