Photographic printing system and method

Claim 1

IN A PHOTOGRAPHIC PRINTING APPARATUS FOR PRODUCINGPHOTOGRAPHIC PRINTS FROM TRANSPARENCIES ON LIGHT-SENSITIVE PRINTING MATERIAL, IN COMBINATION, (A) PROJECTING MEANS FOR PROJECTING AN IMAGE OF A TRANSPARENCY TO AN AREA AT WHICH A LIGHT-SENSITIVE PRINTING MATERIAL IS TO BE LOCATED SO AS TO BE EXPOSED AT SAID AREA TO LIGHT PASSED THROUGH SAID TRANSPARENCY; (B) ADJUSTABLE INTENSITY VARYING MEANS COOPERATING WITH SAID PROJECTING MEANS FOR ADJUSTING THE INTENSITY OF THE ILLUMINATION OF SAID AREA, SAID ADJUSTABLE INTENSITY VARYING MEANS HAVING A GIVEN RANGE OF ADJUSTABILITY; (C) ADJUSTING MEANS FOR ADJUSTING SAID INTENSITY VARYING MEANS AND INCLUDING SENSING MEANS FOR SENSING THE INTENSITY WITH WHICH SAID AREA IS ILLUMINATED BY LIGHT PASSED THROUGH SAID TRANSPARENCY, SAID SENSING MEANS BEING OPERATIVELY CONNECTED WITH SAID INTENSITY VARYING MEANS FOR AUTOMATICALLY ADJUSTING THE LATTER DEPENDING ON SAID INTENSITY SO SENSED SO AS TO PROVIDE WITHIN SAID RANGE OF ADJUSTABILITY AN INTENSTIY OF ILLUMINATION AT SAID AREA WHICH WITH A GIVEN EXPOSURE TIME WILL PROVIDE A GIVEN EXPOSURE; AND (D) TIMING MEANS COOPERATING WITH SAID PROJECTING MEANS FOR PROVIDING SAID GIVEN EXPOSURE DETERMINED AS THE PRODUCT OF SAID ADJUSTED INTENSITY OF ILLUMINATION AND SAID GIVEN EXPOSURE TIME, SAID TIMING MEANS BEING OPERATIVELY CONNECTED WITH SAID SENSING MEANS AND CONTROLLABLE THEREBY FOR PROVIDING SAID GIVEN EXPOSURE TIME IN THE CASE WHERE THE CHARACTERISTICS OF SAID TRANSPARENCY ARE SUCH THAT WITHIN SAID RANGE OF ADJUSTABILITY OF SAID INTENSITY VARYING MEANS IN IS POSSIBLE TO PROVIDE SAID GIVEN EXPOSURE, AND FOR PROVIDING, IN THE CASE WHERE THE CHARACTERISTICS OF SAID TRANSPARENCY ARE SUCH THAT WITHIN SAID RANGE OF ADJUSTABILITY OF SAID INTENSITY VARYING MEANS IT IS NOT POSSIBLE TO PROVIDE SAID GIVEN EXPOSURE, AN EXPOSURE TIME DIFFERENT FROM SAID GIVEN EXPOSURE TIME AND WHICH WITH SAID INTENSITY VARYING MEANS AT ONE END OF ITS RANGE OF ADJUSTABILITY WILL PROVIDE SAID GIVEN EXPOSURE.