Archived posting to the Leica Users Group, 2019/08/14
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Fascinating. Thank you for posting such a detailed response. I wonder what its makers would have thought of your ingenuity. Peter On 13/08/2019 23:20, Alan Magayne-Roshak wrote: > Peter Dzwig asked me about putting X-Synch on my ca. 1917 4x5 RB (Revolving > Back) Graflex. > Here's the story. > > The camera that I bought to go with my 9" f/4 Wollensak Verito Diffused > Focus lens that I got for $12.00 in 1985: > < > http://gallery.leica-users.org/v/Alan+Magayne-Roshak/Gear/MR_Graflex_1_Orig.jpg.html >> > > Side view showing the wiring path: > < > http://gallery.leica-users.org/v/Alan+Magayne-Roshak/Gear/MR_Graflex_2_X-Synch.jpg.html >> > The Graflex has a focal plane shutter with multiple slits and spring > tensions. When the shutter is set to "O" (for open) the film > plane is uncovered but the mirror blocks light from exposing the film. With > a high tension, when the shutter button is pressed, the > mirror flips out of the way, trips the shutter, the entire film area is > exposed for a fraction of a second, and then the shutter curtain comes down > and covers the focal plane. I made some contacts out of Aurora HO-scale > slot car pick-ups and mounted them so that the one on the mirror reset > lever would strike the stationary one at the moment after the mirror was > up, but before the shutter > curtain comes down to cover the film. I can adjust the timing by loosening > the set screw on the arm, and varying the angle > of the moving contact. The wire ends in a standard PC fitting. The lead > going down and inside is for the microswitch in > picture five. > > Closer view with mirror down and shutter cocked: > < > http://gallery.leica-users.org/v/Alan+Magayne-Roshak/Gear/MR_Graflex_3_X-Synch.jpg.html >> > > Closer view with mirror up and shutter tripped: > < > http://gallery.leica-users.org/v/Alan+Magayne-Roshak/Gear/MR_Graflex_4_X-Synch.jpg.html >> > > If I didn't do anything more, the flash would fire again as I reset the > mirror lever for viewing, so in the mirror box I > added a microswitch that only completes the circuit when the mirror/shutter > release lever pushes against it. When the shutter > button is released, the switch opens the circuit and the external mirror > reset lever can swing past the stationary contact without > setting off the flash. > > Microswitch and internal mirror release lever: > < > http://gallery.leica-users.org/v/Alan+Magayne-Roshak/Gear/MR_Graflex_5_X-Synch.jpg.html >> > > I usually like to use this camera with a Graflex 2-1/4 x 3-1/4 roll film > back, so when I'm employing electronic flash, I have > to do this for every shot (except the dark slide only needs to be pulled at > the start and pushed in at the end of the roll). > > 1. Have shutter set to "O" and mirror down. > 2. Focus and compose (remembering to orient the roll film back to match > rectangles for vertical and horizontal shots drawn on the ground glass). > 3. Trip shutter. > 4. Wind film to next frame (there's no double-exposure prevention). > 5. Reset mirror to viewing position. > 6. Rewind shutter to "O" position. > 7. Steps 2, 3, 4, 5, & 6 for each of the remaining seven frames. > > Simple. > - > Alan > > Alan Magayne-Roshak, Senior Photographer > University of Wisconsin-Milwaukee Photo Services > (Retired) > UPAA Photographer of the Year 1978 > UPAA Master of the Profession 2014 > amr3 at uwm.edu > http://gallery.leica-users.org/v/Alan+Magayne-Roshak/ > > "All the technique in the world doesn't compensate > for an inability to notice. " - Elliott Erwitt > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information > -- Dr. Peter Dzwig