Shutter Speeds - Representations in For Sale Ads

[catalinajack]

A recent posting in the "for sale" section stated that the shutter sounded accurate at all speeds. Sounded? Really? Since when is the human ear able to discern the accuracy of shutter speeds as fast as 1/500 of a second. Of course, it's impossible, at any speed. Over the course of several years I have personally tested about 15 shutters (Graflex, Supermatic, serrated-ring Copals, more modern black-rings Copals). Additionally, I have had about 10 shutters professionally CLA'd (Flutot's and Grimes). Not a single one tested to factory specs, especially at the higher speeds. My experience is, and that includes modern Copals, that the best one can hope for is about 1/350 at the high end and that the 1/250 speed is unlikely to be more than about 1/200. Most LF photographers I believe don't use the higher speeds anyway so this may be of little relative importance in the end but I do wish sellers would refrain making such representations as newbies may not be as aware of the pitfalls of purchasing used shutters.

Perhaps others here have had a different experience. Comments?

[Daniel Stone]

That's why I bought a shutter speed tester. That way (I) know *exactly* what I'm working with on each shutter(I test bi-monthly, or before a trip), and write down timings on a small notecard for each lens.

If I re-sell any more equipment down the line, I'll test the shutter's speeds and post the speeds(generally an average of 3 individual simultaneous actuations in a row), as well as include a card with the lens for the new owner.

$100 for a tester is much better than lost shots due to inaccurate calculations before venturing out. I'd rather have empirical data to go on with mechanical items, like shutters, which can lose/change time...

just my $.02

-Dan

[Doremus Scudder]

I don't know about you, but I can sure hear if the shutter speeds are off by a great deal, e.g., if the slow speeds are really too long, or if the intermediate speeds are way to fast (indicating a shutter defect).

Hearing that there are no major issues with shutter speeds just means that, yes, the speeds might be off a bit and the shutter might even need a CLA, but nothing is majorly wrong with the shutter and it is likely serviceable as-is for less-demanding applications.

How often do you test your shutters anyway? I might get the shutter tester out once a year and see how all my shutters are doing. If they don't seem to be in need of servicing, I'll note the actual speeds on the lensboard and use them, but usually they aren't more than a fraction of a stop from marked with the exception of the very fastest speeds, which are inaccurate by design limitation.

So, I think it's perfectly valid to say a shutter "sounds accurate" as long as we don't expect more than a rough assessment from those words.

Best,

Doremus

[goamules]

If you tested all these shutters and they're off, and had other ones CLA'd and they're off still that tells me one thing. It doesn't matter if they're off. Hundreds (used to be thousands) of photographers are shooting fine photos with shutters that are always substantially out of spec. I wouldn't even try to test the repeatably or accuracy of a Packard shutter or my lenscap method where I count seconds in my head. Film must not notice (especially black and white that has a 4-6 stop range). I guess shutters sounding accurate is good enough.

[goamules]

You'd be surprised how accurate human senses are. I can hear a shutter is working more or less fine for government work, up to 1/25th or so. I can watch the light coming through, actuating the shutter held up to a window and corroborate that, and check the faster speeds pretty well too. I don't care if 1/500 is really 1/400 or even 1/300. I don't notice and my pictures don't notice.

[Bob Salomon]

A shutter is in spec at ± 30% of the marked speed.

[biedron]

The phrase "shutter speeds sounds accurate" is also one of my pet peeves. When I have sold lenses I usually say something to the effect that exposures I have made with the lens using the marked speeds have been properly exposed.

I have also bought used lenses described as "sounding accurate" and have had no issues based on the "properly exposed with the marked speed" criterion. But there's wiggle room here too, since exactly what is "properly exposed"? If the shutter was off by 1/3 stop, you'd probably not notice in most exposures. And even if you did, could you be sure your metering of the scene was "correct" to 1/3 stop? Maybe in the studio, but out in the field that seems doubtful. And in the field I'm not sure I've ever used faster than 1/8 second, so if faster speeds were off I'd never notice or care.

Bob

[mdarnton]

Given that no lens will be 100% on, I find the "shutter speed sounds accurate" does indeed have a place in the sliding scale of descriptions of accuracy. I'd certainly have that rather than nothing at all.

[Jody_S]

I have gone through about 1,000 shutters, mostly leaf but some cloth focal-plane, in the last 5 years or so. I do not own a shutter speed tester. I test by ear and by sight (looking through the lens&shutter). I can most certainly tell if a shutter is 'off' enough to affect photos, in all but the most demanding of settings (if you're shooting chromes across lenses and expect to match highlights perfectly, you'd better do your own testing first).

If, as the op says, most leaf shutters do not reach their top speeds, and as far as I know this is true of even new shutters, then this is the norm, and not the fault of the seller of used lenses. And from what I know about shutters, there is no way to make that shutter perform at nominal speed. If you count the proportion of light blocked by the shutter blades as they open and close, and you're measuring the light through the center of the lens, then 1/350 might even out to 1/500 anyway, if you're shooting at full aperture (and you most likely are, if you're using 1/500).

When I say the speeds 'sound' right, what I really mean is that 1s is pretty close to 1s, and the remaining speeds are proportional. That is, 1/2s is 1/2 the length of 1s, and 1/125s is half the length of 1/60, etc. Tested by sound on the low end, visually on the high. Still better to test in real-life situation with film, though. I may make a rig some day to test with a dSLR on Bulb, shooting through vintage shutters.

[DrTang]

when I sell something and state the shutter 'sounds' okay

I'm saying the speeds sound as they are all all different - and they are working - slow speeds sound slow, fast speeds sound fast

meaning ..no.. I haven't had it CLA - and that's why I'm offering it for 80 bucks less than I would had I sent it away


it means YOU should have it CLA if you are a stickler and it will most likely adjust up pretty nice