GB953195A - Apparatus for optically printing photographic negatives - Google Patents

Apparatus for optically printing photographic negatives

Info

Publication number
GB953195A
GB953195A GB3977760A GB3977760A GB953195A GB 953195 A GB953195 A GB 953195A GB 3977760 A GB3977760 A GB 3977760A GB 3977760 A GB3977760 A GB 3977760A GB 953195 A GB953195 A GB 953195A
Authority
GB
United Kingdom
Prior art keywords
photoresistor
condensers
charged
printing
lamps
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB3977760A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
FABAG FOTOGEWERBLICHE APP BAU
Original Assignee
FABAG FOTOGEWERBLICHE APP BAU
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by FABAG FOTOGEWERBLICHE APP BAU filed Critical FABAG FOTOGEWERBLICHE APP BAU
Publication of GB953195A publication Critical patent/GB953195A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
    • G03C5/08—Photoprinting; Processes and means for preventing photoprinting
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B27/00—Photographic printing apparatus
    • G03B27/72—Controlling or varying light intensity, spectral composition, or exposure time in photographic printing apparatus
    • G03B27/80—Controlling or varying light intensity, spectral composition, or exposure time in photographic printing apparatus in dependence upon automatic analysis of the original

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Light Sources And Details Of Projection-Printing Devices (AREA)
  • Control Of Exposure In Printing And Copying (AREA)

Abstract

953,195. Photo-electric control of photographic printers. FABAG FOTOGEWERBLICHE APPARATEBAU A. G. Nov. 18, 1960 [Nov. 19, 1959], No. 39777/60. Heading G1A. [Also in Division G2] In a photographic printer using exposure of the printing paper through the negative and also directly a component in a photo-electric control circuit is switchable so that the two forms of illumination affect the control circuit to different extents. The printing surface 23 Fig. 1 is exposed uniformly by a lamp 35 and through the negative 21 by a lamp 25. The partially transparent mirror 28 has n% transmission when n >50, with the result that equal quantities of light falling on surface 23 from lamps 25 and 35 will produce outputs from the photoresistor 30 which are in the ratio (100 - n / n)<SP>2</SP>. Initially, switches 53 and 44 are closed, the paper 23 exposed uniformly and the condensers 42 and 43 charged by the photoresistor current. After a predetermined time switches 53 and 44 are opened and switch 50 closed. Printing proceeds and condenser 42 is charged until a thyratron 45 fires to open a relay 49. If C 1 and C 2 are the capacities of condensers 42 and 43 respectively to counteract the different effects on photoresistor 30 of the light from lamps 25 and 35, but the ratio may usefully differ from this value when strong uniform exposures are used. A modified circuit, Fig. 2, (not shown) includes two condensers connected in series and each charged during one of the exposures.
GB3977760A 1959-11-19 1960-11-18 Apparatus for optically printing photographic negatives Expired GB953195A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEA33334A DE1109022B (en) 1959-11-19 1959-11-19 Apparatus for the optical copying of photographic negatives

Publications (1)

Publication Number Publication Date
GB953195A true GB953195A (en) 1964-03-25

Family

ID=6928122

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3977760A Expired GB953195A (en) 1959-11-19 1960-11-18 Apparatus for optically printing photographic negatives

Country Status (3)

Country Link
CH (1) CH385007A (en)
DE (1) DE1109022B (en)
GB (1) GB953195A (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1182051B (en) * 1962-05-29 1964-11-19 Pako Corp Photographic light meter for a photocopier
DE1218281B (en) * 1962-06-26 1966-06-02 Gretag Ag Photographic copier with exposure control
DE1202633B (en) * 1964-06-03 1965-10-07 Mikrofilm Ges Mit Beschraenkte Process for an automatic light control in microfilm recording devices for recording documents, drawings, etc. like

Also Published As

Publication number Publication date
DE1109022B (en) 1961-06-15
CH385007A (en) 1965-02-26

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