Calumet Shutter Tester for $109

Ship time is 6-12 weeks if they have the parts in stock to build it..
 
erikhaugsby said:
Speechless good or speechless bad?
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Definitely for good. First I didn't know such a device existed for consumers purchase. Then the price looks very affordable for the lonely RFF member in need of calibrating several Kievs.

I still think that the defitive proof of shutter performance after calibration it is in the X-Ray Test. But using this device from Calument, may shorten the number or test rows.

And lastly, from contrasting the Calumet tester to our sacred negative results, we can learn the byass of the tester, if it exists and I bet it does, and apply this equation for random tests long after final calibration, i,e, vigilance.

What do you think ?

Cheers,
Ruben
 
Russ Pinchbeck has a circuit diagram for a shutter speed tester here on his site, so if you've got an oscilloscope or alternatively a computer with a soundcard, you can have the same for $5 plus a laser pointer.

At home in Germany I've got one lying around as a project with two laser pointers that hooks up to a sound card's stereo jack and allows measuring shutter speed as well as uneven motion of the curtains (i.e. shutter banding). When I'm back this fall I hope I get around to documenting this.
 
rxmd said:
Russ Pinchbeck has a circuit diagram for a shutter speed tester here on his site, so if you've got an oscilloscope or alternatively a computer with a soundcard, you can have the same for $5 plus a laser pointer.

At home in Germany I've got one lying around as a project with two laser pointers that hooks up to a sound card's stereo jack and allows measuring shutter speed as well as uneven motion of the curtains (i.e. shutter banding). When I'm back this fall I hope I get around to documenting this.
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Philipp,
The whole issue is that I am not even far from starting to begin to understand what Russ is showing there. The whole idea of the Kiev Project is the exact opposite, to enable the absolute beginner to achieve a great leap forward, hopefully picking up some in-the-middle knowledge folks during the trip. The beginner is not a stupid, but an intelligent person in front of whom you are tested for your capacity or uncapacity to show him/her the way, starting with the language he/she understands. Otherwise you are showing off yourself only.

Cheers,
Ruiben
 
Michael I. said:
it is actually very easy to make for something like 10-15$
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I am ready to buy from you now at $40. Are you ready to build one for me ?

Cheers,
Ruben
 
BTW, I forgot to mention that my father worked all his life as a travel agent and therefore was able to travel worldwide almost for free, including the best hotels. Unfortunately he lacked the wisdom to offer me a ticket to visit my mother, whom he left overseas before marrying for second time.

I work in the printshop industry and therefore I can print my book at prices you den't ever start to imagine. Not to speak that since I was born is South America, I know Spannish without paying to Berlitz.

People at the right position in the bussiness can and do and do indeed astronomical fortunes in the stock market. Not to speak about the fortunes politicians in the right place can do .

Therefore, respected circuit builders, do you understand what I am trying to tell you ? I am not sure, so I will put it in blunt words: the issue is not at all what can you do for yourself within your waters. The issue is what can you do for all those outside your waters. Otherwise what it matters?
 
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ruben said:
issue is not at all what can you do for yourself within your waters. The issue is what can you do for all those outside your waters. [...] Otherwise you are showing off yourself only.
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OK, so I will try to explain things a little bit. In all openness, however, I want get two things said before that. Firstly, in all honesty, I don't quite appreciate being told that I am showing myself off in this way. Secondly, please remember that there are multiple kinds of waters one can be in. For example, you are apparently in the position to spend $109 on a device, which I am not - one might see this as yet another instance of your waters being not identical to mine, and I don't feel particularly bad for looking for a solution which is within my own waters, which doesn't include $109, but which does include reading some circuit diagrams. Having accepted that people are in different waters, we can thus see that all we are really getting upset about here is multiple solutions to the same problem for people in different waters. DIY Shutter speed testers are for people who can read circuit diagrams, readymade shutter speed testers are for people who have $109 of disposable income, and the X-ray test is for people who have a reference camera and some time to spare.

This being so, here's a little explanation how DIY shutter speed testers work. What these devices do is to provide a sensor, which delivers an electronic signal indicating whether the shutter is open or closed. This signal has a duration, which is the inverse of the shutter speed; meaning that if your shutter is set up all right, for example at a speed of 1/30 of a second, the signal will have a duration of precisely this 1/30, or in decimal terms, 0.0333... seconds. At 1/10, it's 0.1 seconds, and at 1/1000 it's 0.001 seconds. So when, for example, on this website the signal has a duration of 0.067 seconds, we can divide 1 by this 0.067, getting 14.92, which means approximately 1/15 of a second with reasonable accuracy.

When we want to do this measurement, we have two problems. The first is to build the sensor, the second is to actually measure the signal duration.

The first problem, the sensor, requires some electronics. Camera shutters are built to shut off light, so the most obvious way to read the shutter duration is an optical sensor which reacts to light being shut off. Optical sensor arrangements usually consist of a sender unit that emits light, and a receiver unit that detects if light is falling on it. For the sender, most people seem to use a laser pointer, because they are very cheap and ubiquitous, and because they emit a reasonably narrow bundle of light that allows us rather precise positioning of the sensor. For the receiver, most people tend to use a phototransistor, which is basically a device that allows current to pass through when light is falling on it and that reacts reasonably fast (incidentally it is a similar kind of sensor that is used for most modern light meters). So the basic receiver setup would consist of a circuit with a battery (as a source for the current), then the phototransistor (as a sensor that allows the current to pass or not) and then some external way of detecting whether there is any current coming through the sensor. Measuring can be done with an oscilloscope, as Russ Pinchbeck is doing, but it requires an extra device which not everybody has. However, most of us have access to a computer with a sound card. A sound card has an input jack for audio signals, which is a basic, but sufficient way of getting our sensor output into the computer. So most DIY shutter speed testers tend to consist of a battery, the phototransistor and a cable with an audio jack at the end to the computer.

In practice, due to the electrical properties of the computer's sound card input, we need some small extra things here. Take a look at the circuit diagram on this site, for example. The battery and the phototransistor are "polar" devices, meaning that we have to take care in which direction we are using them and which end we are connecting where. The battery is on top, labeled "1,5V"; its "plus" end is connected to the phototransistor's "collector" pin (sort of the transistor's "input"). The battery's "minus" end is connected to one wire of the audio cable to the computer; the phototransistor's "emitter" pin (its "output", so to speak) is connected to the other wire to the computer by means of a small capacitor (here, a 4300 pF or pico-Farad capacitor) due to electrical properties of the soundcard input; for the same reason, the "emitter" pin and the "minus" end of the battery need to be connected with a resistor (here, a 4000 Ohm resistor). This circuit is very easy to build; if you want, you don't even need a circuit board, all you need to do is to solder the ends of the individual components together and put them in some kind of case with a hole for the phototransistor. What this circuit does is that when light falls on the phototransistor, the phototransistor lets a current from the battery pass through to the computer's audio jack; the beginning and end of this signal are visible as two spikes, one upwards and one downwards, as indicated on the small drawing below the circuit diagram.

Assuming that we've built this little circuit and put it into some kind of case. Now what we do is to set the the camera on a tripod (or some other way of fixing it), set the shutter to "B" and hold it open with a cable release. Then we put the sensor on one side of the camera and a laser pointer on the other, so that the laser pointer shines into the sensor. The whole thing should be reasonably fixed so that we can rewind the camera and repeatedly cock the shutter.

Now for the second problem. We have a signal being passed into our computer; what we want to do now is to record and measure it. Since the signal is passed through our audio input jack, for the computer it looks like an audio signal (and if we hooked up the cable to our stereo instead, we would be able to hear the shutter open and close!). The easiest way to do this measurement, then, is that we use some audio recording software (such as CoolEdit 96; an alternative that is IMHO better is Audacity, which is free to download, easy to use, and exists for most computer platforms). We set the software to "record", then fire our shutter (the signal from the shutter speed tester gets recorded), then we stop our recording. Now what we have is an audio file that contains the signal from our tester. Our audio recording program should allow us to look at the waveform of the signal we just recorded; in this waveform we see two spikes: one at the start of the signal (the first light falling on the sensor), one at its end (the light being shut off; due to the characteristics of the sensor itself, the spikes aren't completely straight, but trail off a bit to the edges). Now all we have to do is to select the area of the audio file between the first and the second spike, and our audio recording program will show us the length of the selected area. For example, in Audacity, the screen should look like this screenshot, and in the status bar in brackets we see the duration (0:00,06631, meaning zero minutes and 0.066 seconds). Dividing 1 by this duration, we get the shutter speed, here a reasonable 1/15 of a second. When Russ Pinchbeck's tester gives him 811 microseconds, that is 0.000811 seconds; dividing 1 by 0.000811 shows us that his Kiev has a shortest speed of 1/1233, which is close enough to the 1/1250 in the specification. We can even save the signals to have references for our shutters at various speeds.

An extended version can be had if we realise that our sound card actually has a stereo input, meaning that we can process two signals at the same time. We then need to build a minimally more complicated circuit with two phototransistors, two resistors and two capacitors, and a cable with three wires that has a stereo jack at the end (I don't have a way here of drawing circuit diagrams, but maybe a kind soul can do that for me.) Assuming that we build this in a small case and have two laser pointers, we can then place one sensor so that it measures the duration at the beginning of the shutter's travel, the other at the end. For Leica-style horizontal shutter, this means placing them next to each other horizontally; on a Contax-style vertical shutter they need to be placed vertically. (As the shutters have different widths and heights, if we want to adjust many cameras the easiest thing to do is build two testers with different distances between the phototransistors, one for horizontal and one for vertical shutters.) When we record this audio file, we get one with two stereo channels (one left, one right) with separate signals in each, one from the beginning of the shutter's travel, one from the end (I'll refer to these as the BEGIN and END signal, each consisting of an opening and closing spike as shown above). With this, we can now do several wonderful things. Firstly, the shutter should be open for more or less the same duration at the beginning and at the end - if it is not, it means that the two shutter curtains are not running at the same speed. If the first curtain is faster than the second one, the END signal will be shorter than the BEGIN signal, as the second shutter curtain takes longer to block the light; if the second curtain is faster, it will be the other way round. So we have now an easy way to accurately measure shutter banding! Secondly, we can use this to adjust flash sync times. For flash synchronisation, the shutter has to be completely open. For example, we see the BEGIN signal's opening spike; now the first curtain is starting to open. The first curtain has completed its travel when we see the opening spike also from the END signal. Now we look for the closing spikes. We see the BEGIN signal's closing spike when the second curtain closes the shutter. Our shutter is completely open between the opening spike of the END signal (when the first curtain has opened completely) and the closing spike of the BEGIN signal (when the second curtain is starting to close).

So with this sort of arrangement, with very little money and a low amount of soldering and calculation we get a very flexible device that allows us to do all sorts of measurements. And the electronics aren't actually all that complicated either! ;) Now while I probably have been showing myself off yet again, hopeless individual that I am, I hope that I've done so in a way that actually might be a little helpful in understanding the $5 alternative to the $109 solution :)

Philipp

EDIT: Fixed some links.
 
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rxmd said:
...

So with this sort of arrangement, with very little money and a low amount of soldering and calculation we get a very flexible device that allows us to do all sorts of measurements. And the electronics aren't actually all that complicated either! ;)

...

Philipp
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Well done, Phillipp! :)

.
 
I had never been aware that such devices were even available to the public. The ONLY place I've ever seen one was at a fair in a demonstration booth. A friend of mine even had them put his camera on and run through the speeds. The readouts came up in red numbers.

But I wonder how much value such a piece of equipment has for most people. Given that film (remember that stuff?) has a certain amount of leeway, to say nothing of current playing in Photoshop or similar software, does a shutter speed that is a little off really matter?

Once upon a time Pop Photo had a guy named Goldberg who used to totally disassemble cameras and show a photo of all the pieces. It was part of a test report, in the days of all-mechanical shutters, and he used to run a graph showing how far off each speed was, by percentages. I suppose itwas mildly useful, but would another sample of the same camera perform the same way?
 
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Good post, rxmd. I've been meaning to build one of these for a while now, and think I'll get started today.

" if we want to adjust many cameras the easiest thing to do is build two testers with different distances between the phototransistors, one for horizontal and one for vertical shutters."

In my mind, the easiest way to do this would be to arrange the two sensors at opposite corners of the frame, perhaps 40mm apart, so you could use the same device for any 35mm camera, regardless of the shutter orientation/design.
 
Ruben

If the Kiev snaps like normal it is nearly 100% sure it is linear accross the negative.

If you have a really old TV, then if you take a photo of the screen, 400 ASA B&W film, f/2 lens, camera held vertically, you can work out the exposure, by counting the lines on the screen visible on the negative. (You get a diagonal band. If the band edges are curves the shutter is accelerating.)

I might have an example to post Monday week - I'm off on business till then.

Noel
 
Hi Philipp,
You have given us, non electronic minds, a great service. After reading it twice, I still can't follow everything but I can get the general idea quite well. On this basis, I can either start searching of the things missing from my understanding, or ask any friend in my country to perform the job for me, with me giving the photographic aspects. You have built a bridge towards the one without knowledge of electronics.

You have done a great and patient effort I appreciate a lot.

As for the showing off issue, incidentally I was not refering to your post in which you made some basic starting commentaries or explanations, but to the posts by Mohan and Michael. What was bluntly lacking in their posts was to say: "Because I have some knowledge or deep knowledge of electronics I can build and you can build a ten dollars tester provided you too have some minimal knowledge of electronics. If you don't have any knowledge of electronics I am not going to make any effort towards you so go to somewhere else". That would have been better than saying "it is easy".

Most of the chances are you may not accept my explanation and perhaps I may discover later I have been too harsh, or impulsive, or over-reacting. And I will be eagerly continue talking on this aspect with you, as even when you protested my teasing you have done it in a very self restrainig way, I must remmark. Your long post is not just a technical one, but a show of a kind soul.

Overall, let me say I remain extremely thankfull for your contribution.

Cheers,
Ruben
 
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Ruben:

I picked up one of these testers a couple of years ago. While I can't complain about the functioning of this device, it is quite crudely constructed -- it truly looks like some 8th grader's science fair project that was hastily assembled the night before the assignment was due.
 
ruben said:
As for the showing off issue, incidentally I was not refering to your post in which you made some basic starting commentaries or explanations, but to the posts by Mohan and Michael. What was bluntly lacking in their posts was to say: "Because I have some knowledge or deep knowledge of electronics I can build and you can build a ten dollars tester provided you too have some minimal knowledge of electronics. If you don't have any knowledge of electronics I am not going to make any effort towards you so go to somewhere else". That would have been better than saying "it is easy".
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I think you mis-understood. For some of us who don't have a spare $109, the time spent searching and reading and trying are all we have. The fact that others are willing to testify that it can be done with little effort and low cost is not "showing off," it is "mutual support." At least, that's how I read it. Nobody was claiming they were electrical engineers who could do it in their sleep, rather merely implying that a "regular guy" could do this project in their spare time.

Consider your own posts re: Kiev disassembly might come across the same way you refer to Mohan and Michael's posts, if one were prone to seeing things that way :)
 
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