Testing the Rebuilt Shutter
Having rebuilt the shutter, I was feeling pretty good about things, but wanted to make sure the shutter speeds were in fact firing accurately. The same camera shops that had been unwilling to work on the camera were not interested in testing it either (no big surprise here). I looked into ordering the cheap version of the pocket shutterspeed tester sold by Fargo Enterprises (incidentally, they appear to have about everything you could want for camera repair if you have the budget for it). Unfortunately I couldn't justify to myself the cost of the tester, given that if I got the repair right, I'd not need the tester again for quite some time. I considered simply shooting chromes of test charts to get a ring-around, but the cost of the materials didn't seem a wise investment either. Eventually, I remembered something about video refresh rates from when I worked for a video company. I did some looking, and sure enough, came up with the time it takes for a standard North American TV set to paint a single line of dots across the screen (62 or 66 microseconds per line, I forget which now). I was set. I picked up my Polaroid back (instant gratification being what it is), loaded it up with a sheet of B&W film, turned the room lights off, the tv set brightness to max, and proceeded to shoot a couple of frames at different shutter speeds, counting the lines that appeared in each shot with a loupe. I had a winner, the shutter was tight enough to shoot print without problems, and appeared consistently close enough to make passable chromes..