How does one make sure of proper shutter speed?
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Fraser
Well-known
well all my cameras are either remove or hinge back, tried the little gadget for iphone to test but much harder to use than dslr method.
sevo
Fokutorendaburando
Proper shutter time measurement is surprisingly difficult, as shutters are not really on-off, but have a life of their own. The DIY single cell/single beam testers now common will not tell you about FP shutter fading, nor will they give correct time-equivalent results for leaf shutters.
I have a 1970's Kyoritsu tester (a device the size and weight of a drill press), which already used a matrix of five photo transistors to have reasonable accuracy on 35mm focal plane shutters - the same arrangement is of very limited value when it comes to testing the short times on a leaf shutter, and current testers are even less complex.
My advice would be to test EXPOSURE, on film, first of all! If there is a visible irregularity in a time-vs-aperture series, you can test the affected times with one of the now available devices. Do not forget to cross-check against the film - if the measurement gives one stop error while the film is a third stop off, trust the film, and adjust your test methodology.
I have a 1970's Kyoritsu tester (a device the size and weight of a drill press), which already used a matrix of five photo transistors to have reasonable accuracy on 35mm focal plane shutters - the same arrangement is of very limited value when it comes to testing the short times on a leaf shutter, and current testers are even less complex.
My advice would be to test EXPOSURE, on film, first of all! If there is a visible irregularity in a time-vs-aperture series, you can test the affected times with one of the now available devices. Do not forget to cross-check against the film - if the measurement gives one stop error while the film is a third stop off, trust the film, and adjust your test methodology.
zuiko85
Veteran
Easy! Drill a 1/4 inch hole through the back of the camera and pressure plate for the tester to look through then just cover the hole with black tape when your through.
Just kidding and couldn't resist a silly reply.
radi(c)al_cam
Well-known
Excellent!
But, if I don't have a TV, or a cathode ray tube («CRT») computer monitor, does it work with a newer monitor too?
MIkhail
Well-known
I don’t believe so.
That’s a good idea. This way you can come back and re-test again later.
benlees
Well-known
I think there is an app for that. They do it by sound, I believe.
Calzone
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A friend who worked for Nikon repair in N.Y. taught me how to test one second and with experience it gets really reliable. For me in one second I can count aloud one-seven. For a reference I can use the highly accurate electronic shutter of one of my Nikon F3's to get the cadence.
On my M6 I had my camera looked at by Nippon. At that time the fast shutter speeds were deemed off, which seem to be the first to go. By the time the slow speeds are off you can kinda know the fast speeds are likely way-way off. Anyways this is on a well used camera.
Also on M-body Leicas when testing one second there is a whirling run on that kinda reveals the overall condition of the shutter.
Anyways electronic shutters are timed by quartz crystals and stay accurate. Anyways consider a M7 for shutter accuracy.
Cal
coelacanth
Ride, dive, shoot.
Since I shoot b/w negative only, I never really had to worry too much about shutter speed accuracy beyond "sounds about right." For me, bigger issue over the years has been the curtain opening consistency specifically on Leica cameras with cloth shutter curtains. Inconsistent "shutter speed" during an exposure resulting in unevenly exposed photos was a headache to deal with in the past, as well as some cameras exhibiting bounce-back issue. Would be nice to know how one can check that without sending it for service or film testing.
froyd
Veteran
Yes Benlees, there's an app for that.
https://itunes.apple.com/us/app/shutter-speed/id560154244?mt=8
and
https://play.google.com/store/apps/details?id=com.plug.photo.shutter_speed&hl=en
Requires a hardware plug.
Here is the developer's website: www.photoplug.de
https://itunes.apple.com/us/app/shutter-speed/id560154244?mt=8
and
https://play.google.com/store/apps/details?id=com.plug.photo.shutter_speed&hl=en
Requires a hardware plug.
Here is the developer's website: www.photoplug.de
Fraser
Well-known
Timmyjoe
Veteran
That's the one I use
Fraser
Well-known
Its to do with the refresh rates I think, I've used that method in the past and its good for checking consistency, but I still think the dslr method is by far the most accurate short of buying a proper shutter tester.
wolves3012
Veteran
If you don't have access to a proper shutter speed tester, you can use the computer CRT monitor test. That's if you can find a CRT monitor! It won't work with an LCD screen and it's not much use for speeds under 1/125 either. I've used it and found it informative, since it can show you capping and uneven exposure. It won't give you an accurate figure for speeds though.
Despite what's said above, I can certainly hear the difference between 1/250 and 1/60, to me it's blatantly obvious. I can also hear the difference between 1/40 and 1/60. What I can't do and I seriously doubt anyone can do is to hear the difference between (say) 1/260 and 1/250. Nor can I pin an accurate number on a shutter speed just from sound, especially over 1/250. Actually, I think folk obsess excessively about accurate speed too.
When sellers say "all shutter speeds correct" and so forth, I suspect they mean all speeds appear to sound approximately correct or give appropriate exposures with film. Frankly, it's what I would assume unless they state, explicitly, it's been tested on a pro shutter tester.
Despite what's said above, I can certainly hear the difference between 1/250 and 1/60, to me it's blatantly obvious. I can also hear the difference between 1/40 and 1/60. What I can't do and I seriously doubt anyone can do is to hear the difference between (say) 1/260 and 1/250. Nor can I pin an accurate number on a shutter speed just from sound, especially over 1/250. Actually, I think folk obsess excessively about accurate speed too.
When sellers say "all shutter speeds correct" and so forth, I suspect they mean all speeds appear to sound approximately correct or give appropriate exposures with film. Frankly, it's what I would assume unless they state, explicitly, it's been tested on a pro shutter tester.
MIkhail
Well-known
As I clarified further above, I can hear that they sound differently, I just don't know what they mean (what the 1/250 sounds like, for example?). And even if I cannot hear that... hearing cannot be any indication of accuracy, in my (engineering) world anyway.
Obsessing over the exact speed is not my issue at all. And it is what it is, on the camera that I already own. It is, however, seems useful to know what you are getting from the start, from eBay or otherwise.
I am going to get myself that tested KoFe suggested- seems like a good solution.
johnnyrod
More cameras than shots
I've been using this
http://www.baytan.org/prak/shutter.html
for over a year now, with the program Audacity to visualise the data. I use a spot lamp as the light source, or for curtain shutters, a laser (spirit level, pointer etc.) as the stray light gives false readings. It's cheap and works very well, at more or less any speed -I've measure 1 second up to 1/1000.
As Roger says above, accuracy is surprisingly poor; 20-25% is acceptably close. Many older cameras will actually run at anything up (down?) to half speed though, so an indicated 1/500 is really 1/300 at best, but at least you can get the speeds to cover a range i.e. 1/250 will give about twice the exposure of 1/500, at least it makes sense. I don't bother to correct for the inaccuracy when shooting unless it's really bad or you're struggling to find the right speed.
The error in the accuracy of the apertures is similar though, so without getting into the philosophy (argument) around "correct" or ideal exposure, take it all with a pinch of salt.
Oh and I think a lot of sellers say "the speeds sound right" when 1/30 still snaps instead of stalls, and 1/125 sounds faster than 1/30
http://www.baytan.org/prak/shutter.html
for over a year now, with the program Audacity to visualise the data. I use a spot lamp as the light source, or for curtain shutters, a laser (spirit level, pointer etc.) as the stray light gives false readings. It's cheap and works very well, at more or less any speed -I've measure 1 second up to 1/1000.
As Roger says above, accuracy is surprisingly poor; 20-25% is acceptably close. Many older cameras will actually run at anything up (down?) to half speed though, so an indicated 1/500 is really 1/300 at best, but at least you can get the speeds to cover a range i.e. 1/250 will give about twice the exposure of 1/500, at least it makes sense. I don't bother to correct for the inaccuracy when shooting unless it's really bad or you're struggling to find the right speed.
The error in the accuracy of the apertures is similar though, so without getting into the philosophy (argument) around "correct" or ideal exposure, take it all with a pinch of salt.
Oh and I think a lot of sellers say "the speeds sound right" when 1/30 still snaps instead of stalls, and 1/125 sounds faster than 1/30
sevo
Fokutorendaburando
That is often a side issue of the measurement methods - times for narrow slit widths on FP shutters and short times on leaf shutters both have to take into account that the shutter may also act as a variable aperture in these modes, if the blurred edge respective opening/closing take up a relevant part of the total. The absolute time measured may be longer than nominal, but can result in a exposure equivalent to the nominal.
Richard G
Veteran
"All speeds sound correct" is not entirely useless information on a Leica. Each M Leica speed has a different sound. The slow speed running slower and unevenly is often a sign of poor lubrication and a need of a service. My M5 1/2s is slower than 1/2s, even though it was serviced by DAG before I bought it. I can live with that. My M6 and M2 are good, and the M2 was serviced very precisely in the last ten years.
Determining the difference between adjacent speeds (Eg 1/125-1/250) is possible with enough experience, by ear. Most focal plane shutters are going to be moving at the same velocity across the gate at the faster speeds but they will produce a different sound when the exposure ends. It's because the interval between the first and second curtain capping varies with whatever slit width is used for the speed in question. Admittedly, with some SLRs the noise of a reflex mirror descending may make it harder to work out the exact moment of the second curtain capping. A tip here, if your SLR actually has a mirror lock up feature, is to use it, because it makes it that much easier for your ear to work out what the shutter is doing, by removing the mirror and its actuating mechanism from the equation.
Using a CRT television it's possible to get a decent idea of how accurate a focal plane shutter is, although the more practice you've had using one, the better you will be able to understand and interpret the results. For instance, it enables you to work out which curtain is moving fastest at different parts of the gate, based on the relative angles of the edges of the slit. No, it is nowhere near as accurate as a proper testing unit, and nobody (including myself) would suggest otherwise. But having used the method to set up a number of shutters made by different makers, I do know, from my own experience and results, that it can get a serviceable camera working to within tolerances that will give you well exposed negatives, (or even positives, for that matter) so, it can certainly be accurate enough. And actually, whereas some of the least sophisticated testers may give you much more accurate overall exposure measurement, they may be less useful than a CRT for gauging exposure variance across the gate, something you can actually see with a TV/monitor screen. Non-CRT monitors are unreliable for the above in my experience, I keep a CRT on hand for shutter evaluation.
It's also worth mentioning that checking a shutter for proper operation may or may not entail checking every speed range, anyway. Depending on the design, the maker may specify that once certain speeds have been correctly set, other speeds will be within tolerance. A Synchro Compur type is a case in point. The escapement is first positioned to achieve an accurate one second time, followed by the 1/15 speed, and, when these have been set, the other speeds will then be OK (this, sourced from the relevant pages of F Deckel's repair manual for the shutter). Even setting one up by ear is not really that hard, with enough experience. Why? Because, if the escapement is not located correctly, one second will usually be too short. And 1/15 will be about the same as, or shorter than, 1/30, if the escapement is not set in the best position for that speed. There's only a fairly small zone of acceptable placement for the escapement where both speeds will look and sound right. If you have half a clue about detecting the different times it should be obvious, because, if it is out, it will usually be really out. 1/250 and 1/500 are too close together to be able to detect visually by all but the most experienced eye (I can sometimes see a difference, sometimes not, depending on a few things) and, even then, you usually need the lens stopped right down and pointed into a very bright light source as the smaller aperture helps the eye spot a difference. But the change in pitch of the mechanism from the additional speed of 1/500 is definitely audibly different to 1/250, it is a slightly higher pitch, which is a result of the escapement being totally disengaged at the maximum speed (at 1/500 the shutter is running as flat out as the main spring will let it, without any inertia braking).
With all that said, a decent tester makes it possible to achieve not just more accurate results, but to do it faster and more consistently. Which is why I'll probably be purchasing one of these units later this year. It's going to save a lot of time, quite apart from the other benefits. And because it is also able to measure curtain velocity of each focal plane shutter curtain, not just the amount of exposure, I think it will assist in the adjustment of the appropriate curtain(s) first time around and save a lot of time. As some manufacturers are helpful enough to specify an actual velocity target for the curtains of some of their designs, being able to easily measure this, should, again, substantially shorten the amount of fine tuning needed to get such shutters bang on, in the minimum amount of time.
Cheers,
Brett
Using a CRT television it's possible to get a decent idea of how accurate a focal plane shutter is, although the more practice you've had using one, the better you will be able to understand and interpret the results. For instance, it enables you to work out which curtain is moving fastest at different parts of the gate, based on the relative angles of the edges of the slit. No, it is nowhere near as accurate as a proper testing unit, and nobody (including myself) would suggest otherwise. But having used the method to set up a number of shutters made by different makers, I do know, from my own experience and results, that it can get a serviceable camera working to within tolerances that will give you well exposed negatives, (or even positives, for that matter) so, it can certainly be accurate enough. And actually, whereas some of the least sophisticated testers may give you much more accurate overall exposure measurement, they may be less useful than a CRT for gauging exposure variance across the gate, something you can actually see with a TV/monitor screen. Non-CRT monitors are unreliable for the above in my experience, I keep a CRT on hand for shutter evaluation.
It's also worth mentioning that checking a shutter for proper operation may or may not entail checking every speed range, anyway. Depending on the design, the maker may specify that once certain speeds have been correctly set, other speeds will be within tolerance. A Synchro Compur type is a case in point. The escapement is first positioned to achieve an accurate one second time, followed by the 1/15 speed, and, when these have been set, the other speeds will then be OK (this, sourced from the relevant pages of F Deckel's repair manual for the shutter). Even setting one up by ear is not really that hard, with enough experience. Why? Because, if the escapement is not located correctly, one second will usually be too short. And 1/15 will be about the same as, or shorter than, 1/30, if the escapement is not set in the best position for that speed. There's only a fairly small zone of acceptable placement for the escapement where both speeds will look and sound right. If you have half a clue about detecting the different times it should be obvious, because, if it is out, it will usually be really out. 1/250 and 1/500 are too close together to be able to detect visually by all but the most experienced eye (I can sometimes see a difference, sometimes not, depending on a few things) and, even then, you usually need the lens stopped right down and pointed into a very bright light source as the smaller aperture helps the eye spot a difference. But the change in pitch of the mechanism from the additional speed of 1/500 is definitely audibly different to 1/250, it is a slightly higher pitch, which is a result of the escapement being totally disengaged at the maximum speed (at 1/500 the shutter is running as flat out as the main spring will let it, without any inertia braking).
With all that said, a decent tester makes it possible to achieve not just more accurate results, but to do it faster and more consistently. Which is why I'll probably be purchasing one of these units later this year. It's going to save a lot of time, quite apart from the other benefits. And because it is also able to measure curtain velocity of each focal plane shutter curtain, not just the amount of exposure, I think it will assist in the adjustment of the appropriate curtain(s) first time around and save a lot of time. As some manufacturers are helpful enough to specify an actual velocity target for the curtains of some of their designs, being able to easily measure this, should, again, substantially shorten the amount of fine tuning needed to get such shutters bang on, in the minimum amount of time.
Cheers,
Brett
Peter Jennings
Well-known
To test for consistency in the shutter opening in Leica-type shutters, I have been using my iPhone lately. Use the slo-mo setting in the camera app and look at the gap from opening to closing during playback. For bottom loaders, slip a piece of white paper behind the shutter curtains.
