Shutter tester mini-review

[picker77]

Curiosity about the real-world speed accuracy of the shutters on my various cameras and lenses finally overwhelmed me, and being too lazy to hunt down the parts and build my own, I ordered a $14 (plus $17 shipping and three week's transit time) phototransistor-based tester from a Romanian gentlemen named Vasily Florin (shuttertester@gmail.com) who sells on the auction place under the name "vfmoto".

After playing with this thing for a few days, I have to say it works like Bob's your uncle. Ridiculously easy to set up and use. Just download Audacity (an excellent little free audio editor from Sourceforge.net), plug the tester into a PC or laptop's mic input, turn on any small, bright single-source light (a cheap little single-LED flashlight is perfect) and go to town with it. It's extremely accurate (to five decimal places or more if you want), and if you've never seriously tested your shutters you might be in for some eye-opening results. I was. Most of my shutters (even the old ones) are surprisingly accurate (and very repeatable) from one second down to around 1/125, but only a few can hack it at 1/250 and only one or two came anywhere near 1/400. Most accurate was a Nikkor-W 210/5.6 in a Copal #1, which was nearly dead on at all speeds. I was shocked to see that some of my worst (on high speeds anyway, med/slow were great) were the Seiko leaf shutters on my RB67 lenses. That was pretty disappointing!

But at least now I know where and how much I need to compensate for better exposures, so it was a valuable exercise.

I have zero financial connection to this person's business, I am just a happy customer. If you want to mess with testing your shutters, I can heartily recommend Vasily's tester, which appears to be carefully built, works fine, and came with a seriously long cord (nearly 10').

[Peter De Smidt]

Thanks for the review.

[Roger Cole]

Thanks for the information; that's very good to know. I may buy one. I had my LF lenses CLAed back in the late 90s when I started LF and the guy who did it provided a printed graph of shutter accuracy (with lines for accepted tolerance) at each speed for each of them. What you report was true then on my just-CLAed shutters too. Fine up to 1/125 or so, progressively running slower at higher speeds, but for LF I almost never shoot shorter than 1/125 and rarely that short.

It would be a cheap way now to test 'em out again and be sure they're still good.

[Revolucion Artistico]

I just bought one off him last week, but am still waiting to get it, so it's good to know it works well and is easy to use. Thanks for the review

[Vladik]

I have to fully agree with picker's review

Another satisfied customer.

Vasily also has a great customer support and is ready to answer any questions.

[picker77]

I looked at many "instant digital readout" testers, usually in the $100 and up (way up) range. But they all still need the same basic setup as this one to use and have more parts that can fail. All this one requires is one more step in the process--you have to use your mouse and a cursor to mark and measure the start/stop pulses on your pc, then read off the number displayed. Because you can zoom the view of the pulse, this is easy. With only a little practice I became consistent and accurate in measuring the pulses. Kind of fascinating, too, to watch the actual shutter opening and closing via the pulse shape. Once you see what the opening or closing pulse shape of a correctly working shutter looks like, you can even tell if shutter blades or curtains are hesitating or hanging up during the actual opening or closing action. I also tested a favorite old mint FED 3b that had been CLA'd by Yuri at FEDKA in New York a couple of years ago. It was pretty accurate overall, but most interestingly it was also reasonably good at the higher speeds, where nearly all my "modern" leaf shutters seemed to struggle. More kudos to Mr. Oskar Barnack and his brilliant design!

[rdenney]

We've had extensive discussions about these testers at quite a technical level, and to summarize, these testers work well in the range where they work well.

I found them to be accurate up to about 1/125 shutter speed. Beyond that, and the response time of the photo-transistor, the DC filtering on the sound card, and the uncalibrated light source, all greatly affect the waveform you see with Audacity. Choosing the correct part of the spike is easy when the shape of the spikes are tiny compared to the distance between the on and off spike, but with higher shutter speeds, those spikes get quite close and then interpreting where to make measurements introduces a lot of potential error.

I have tested the photo-transistor testers, one of my own design based on the online sources and one bought from a trusted ebay seller (both ended up being nearly identical), using an oscilloscope which is both fast and is not subject to the DC and high-frequency transient filtering on the input of a sound card. The resulting spikes therefore represented the actual output of the circuit. I found that the amount of light reaching the transistor could cause it to saturate early in its exposure, or later in its exposure, given different waveforms and making interpretation even more difficult. Again, this is all down in the noise at 1/125 and slower. With this setup I was able to get results I was comfortable with up to maybe 1/500.

The Calumet tester, when used as instructed (requiring one to adjust the light source to fall within a certain threshold), measures accurately to 1/1000 at least. Wally's design seems to be similar, and he has explicitly corrected the issues we have discussed with the transistor tester.

So, it works fine within a certain range, and if one only has Copal 3 and Ilex 4 or 5 shutters, there is no issue. Be careful with higher shutter speeds, though.

Rick "who rarely uses those high shutter speeds with large format in any case" Denney

[cyrus]

Indeed I made one of these using the online instructions and discovered a shutter bounce on one of my lenses!

[picker77]

Well stated, Rick. Vasily claims these can work well up to 1/1000 but my experience with this one at around 1/400 seems to bear out what you said. I have a good electronics bench and a Tek scope, so could have tried that too, but the choke point of an unknown (and maybe variable) response time of the sensor used would still remain, not to mention the probably much larger delay variables built into the audio chain of the sound card/chipset itself. Like you, I have high confidence in measurements taken with one of these up to maybe 1/250, after that I dunno. Since I rarely shoot chromes and rarely use anything faster than 250 anyway, none of this is a major problem for me, just interesting knowledge.

Just for fun, I'm going to put this thing on my F100 and my RF645 today if I can figure out how to make them fire with the backs open.

It's still a marvel to me that camera and shutter makers in the 30's and 40's could come up with precise timing mechanisms that were small enough to fit in a camera or shutter and yet be consistently repeatable through many thousands of cycles.

[GPS]

...

It's still a marvel to me that camera and shutter makers in the 30's and 40's could come up with precise timing mechanisms that were small enough to fit in a camera or shutter and yet be consistently repeatable through many thousands of cycles.

To let you marvel even more think of the fact that in the 30's and 40's precise shutters were already well established in photography. It was after 1912 (Compur) that they became available to photographers.