Polaroid SX70 manual

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partial pack : the top of the sheet of film would be ejected as a dark slide and the counter would registrer «10». After the last actual sheet is used, the camera would still function until «0» is reached. If a flash bar were attached, and an unused bulb was available after the last film sheet was used, attempting to make another exposure would fire the flash.

The difference in the flash mode are :

inserting a flash bar closes S2, which activates solenoid #2 to move the interceptor into position. This controls the shutter blades according to focusing : the closer the subject the more light from the flash will bounce back. Therefore, the smaller the permitted aperture.

At the end of the «Y» delay, a flash delay circuit is activated, and when S4 switches from CB to CA, Ca sends power to the flash circuit. During the fixed flash delay, the photocell and S/T are operative , so that if enough light energy is collected before the end of the flash delay, the blades will be closed as in ambient picture. However, on newer cameras («P» configuration shutters), the flash will fire whether or not sufficient ambient light si available.

At the end of the flash delay (the blades at this point are open to the aperture dictated by focusing) power is removed from solenoid #2 and the discharge (flyback voltage) triggers the flash circuit, firing the flash and starting the flash time out interval (the fixed exposure time). If, on early cameras, an ambient exposure has been made, S/T-2 in the ECM receives the signal and no flash or flash time out occurs.

At the end of the flash time out, the circuitry energizes solenoid #1 which closes the blades. if no flash has occured, caused by all the bulbs having been used, no signal will be sent to solenoid #1, and on early cameras an ambient exposure will be made. If the S/T has not collected sufficient light energy at the end of a fixed period (20 seconds), the blades will automatically close. On newer cameras, the exposure time remains short and a black picture will result.

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Contents Page Page Description General DescriptionCamera Operation Opening the CameraLoading the Film pack Starting the Automatic MechanismSetting the exposure counter Viewing and focusingViewing and shooting Completing the film pack Exposures using flashDeveloping the print Shutter Description Ambient Light Mode Closing the camera11 a Location & Arrangement of internal parts Shutter Description Flash Mode Page 14 S5 being opened by the recock ram Gear train Page Power Source IntroductionLens Viewing and Exposing SystemFresnel Figures 2-3 a and 2-3 B Viewfinder optics exposingFresnel screen Viewfinder MirrorsFlare baffle Camera Elctronics 1. GeneralSwitch functions SX-70 Switch locationsS3 Being opened by recock ram S4 Switch operating configurations Switch Function Table Function SequencePage Flash Timing Sequence Chart Shutter Mechanical Details Figure Shutter, exploded viewA Solenoid S2 operation Film Processing Components Sequence of OperationsPage Max III Troubleshooting Introduction Initial TestsSX-70 Cmaera Repair Inspection Procedure Power supply and pack simulator Figure Test Equipment OperationCollimator Figure Location of new collimator targetDisengaging the idler gear Comprehensive Testers -6 Comprehensive testerModel B Camera tester Model B Camera Tester Comparalumen Light Levels Table Light Leak Tester FigureFlash Simulator Board Figure Light leak test systemManual Function Tester Figure 10 Manual camera testerManual Function Test Sequence Optical System Exit Pupil TestEntrance Pupil Test 13 Aligning the exit pupil gageUSE of Analysis Charts Concave Mirror Distortion CheckFresnel Quality Check Collimation16 Fresnel standards chart Camera/Shutter Isolation 18 Flex circuit terminal locationsCamera Analysis Charts 19 Test points on SX-70 shuttersPage Installation Front COVER/SPREAD Roll AssemblyRemoval Repairs / Adjsutments Loose Front Covers Front cover hinge studsBending the stop latch Top Spread Roll Looseness Interference Between Front and Bottom CoversReplacing the Light Shield Cam Mirror Cover / Boot Assembly Front cover light shield camBoot retaining screws