Shutter maintenance questiongreenspun.com : LUSENET : Large format photography : One Thread
I have a 210mm apo-symmar in a copal shutter, purchased new in 1994, used extensively in 1994 and intermittently through 1998, and unused since the summer of 1998. If I were to start using the lens and shutter today, would I have to worry much about inaccurate shutter timings given the period of disuse? Is it worth bringing it in for a clean/lubricate/adjust? Thanks.
-- Joshua Divack (email@example.com), September 26, 2000
I have used shutters that were in storage for far longer than that (20 yrs), and they work just fine. Go thru each speed a few times, and see how they sound. A few chromes will tell. If it seems inaccurate, then send it in for a CLA.
-- Ron Shaw (firstname.lastname@example.org), September 26, 2000.
The Copal shutters seem to be less prone to sticking than Compurs. Maybe just a different lubrication. I would spend a little time working the shutter at all speeds, especially the lower speeds and then check it out with a few negs or chromes. It might be o.k. as is. Regards, Doug.
-- Doug Paramore (email@example.com), September 26, 2000.
Even if the shutter seems to be working I'd take it in to a camera repair facility or to a camera shop with a leaf shutter diagnostic tool. They can check your shutterspeeds and usually only charge a token fee. I do this once a year for all of my large format lenses to find out where the shutterspeeds have drifted off too. I don't get the shutters "fixed" because I have no confidence that they'll stay adjusted for any length of time. What I do is that I make up a cheat sheet with the actual/indicated shutterspeeds, print it out on the computer and laminate the printout so I can take it with me and refer to it in the field.
You can also put any other useful bits of information on this same sheet and I include reciprocity departure information for all of the films that I'm likely to use.
If you don't do this and just shoot some film you may see that you exposure is off. But you still won't know by how much and whether the error is consistant for each shutterspeed (mine aren't) and then you'll have to the lens in to the camera shop. So I'd suggest that you save some time, money and frustration, and go the camera shop route first.
-- David Grandy (firstname.lastname@example.org), September 27, 2000.
David, do your shutters actually wander that much? I find mine to be quite stable.
-- Ron Shaw (email@example.com), September 27, 2000.
The previous suggestion of having a speed test done, and basing your exposures on the result, is a good plan.
All mechanical shutters are crude affairs, and the chances are that if the 1 second speed is close to one second, then all the rest of the speeds will fall in line.
The Copal/Seiko shutters have a delay train for speeds from 1 second to 1/15th, and a second delay train for 1/30th to 1/400th, and these are all driven from one single main spring 'cock'.
The delay trains are non-adjustable, and as a result they either work, or they don't. What regulates the speeds is a cam that brings the gear train more or less into mesh with the rest of the mechanism.
This cam consists of a fairly crude stamped-out plate. By changing the shutter speed, you're simply rotating this cammed plate relative to a setting pin, which in turn is attached to one or other of the delay gear trains.
What this all boils down to is, that unless someone is willing to take a file to the cam plate, then the speeds cannot be individually adjusted.
Any repairer who says they can correct one speed setting, without altering the rest, is either lying or is going to charge a small fortune for the service.
-- Pete Andrews (firstname.lastname@example.org), September 27, 2000.