FLASH PHOTOGRAPHIC DEVICE

• Main Authors: KAWAMURA MASAHARU, KATSUMA MAKOTO, YAMADA MASANORI
• Format: Patent
• Language: English
• Published: 26.12.1983
• Subjects: ACCESSORIES THEREFOR; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USINGWAVES OTHER THAN OPTICAL WAVES; APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FORPROJECTING OR VIEWING THEM; CINEMATOGRAPHY; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOTDIRECTED TO A PARTICULAR RESULT; DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g.ARRANGEMENTS FOR COPYING OR CONTROLLING; ELECTROGRAPHY; HOLOGRAPHY; MACHINE TOOLS; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OFPARTICULAR DETAILS OR COMPONENTS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; PHOTOGRAPHY; PHYSICS; TRANSPORTING

PURPOSE:To obtain invariably optimum exposure for flash photography by switching a dimming mode wherein the amount of lighting is settled on the basis of a distance and an aperture value to a TTL dimming mode in response to the attachment of accessaries such as a filter and an extension ring. CONSTITUTION:When an accessary such as an ND filter is attached, a switch SW14 is turned on and a mode switching circuit CSW seects a contact (a) regardless of the state of a manual switch SW13. Consequently, the TTL dimming mode is selected and light metering SP1 of film surface reflected light, integration iNT1, and lighting stop signal output CP1 are carried out to stop lighting through a dimming circuit CNT. When no accessary is attached and the manual switch is off, a contact (b) is selected to set the dimming mode. At this time, the amount of lighting is calculated at a part CAL on the basis of distance DVL, aperture AVL information, etc., to perform lighting stop control based upon direct light metering SP2 and integration iNT2.