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Arthur Nichols
19-Mar-2010, 07:11
Anyone try one of these? They look pretty good.
http://cgi.ebay.com/Shutter-Tester-for-Rangefinder-SLR-Leica-Canon-Nikon_W0QQitemZ170423507964QQcmdZViewItemQQptZFilm_Cameras?hash=item27ae085bfc

Matthew Rolfe
19-Mar-2010, 09:29
I haven't used one but I agree they do look pretty good. Did you buy it? That seems a good price.

I'm also interested in other peoples opinions on the device.

BetterSense
19-Mar-2010, 09:55
Too much. I could make a similar device for <30, including LCD readout. I suppose that means I should be in the business myself.

Toyon
19-Mar-2010, 10:00
Too risky. No picture. You would be trading with a lawless country (at least where consumers are concerned).

jwaddison
19-Mar-2010, 10:06
I don't see that there's that much risk. He is an ebay employee, 1400 purchases with 100% positive feedback and he's sold 13 of these gadgets.

Michael Cienfuegos
19-Mar-2010, 10:14
I don't see that there's that much risk. He is an ebay employee, 1400 purchases with 100% positive feedback and he's sold 13 of these gadgets.

I agree. Mr. Zhou is a reputable dealer. I've seen a lot of his stuff, especially his Leica cases, which are quite nice. I know that one of those testers can be made for a lot less, but when you are as handy with a soldering iron as I am, it pays to have someone market this item.

bobwysiwyg
19-Mar-2010, 11:19
Too risky. No picture.

I use Safari and the pic icons down further in the listing can be opened in a new window by right clicking on them.

Sevo
19-Mar-2010, 13:35
I have one of these - works accurately (even more so if you combine it with a laser pointer). It rather looks as if it is a refined small series production of the shutter timer once published by the German/Dutch electronics DIY mag Elektor/Elektuur - which was back then about 60DM for the parts kit and two or three hours assembly, without case or power supply, so $120 is fair, even more so considering that I'd have to spend a couple of hours locating the parts (or current replacements) individually nowadays.

Sevo

Stephane
19-Mar-2010, 14:41
Some guy from another forum used this free audio recording software (I downloaded it, but have not used it). Wat you do is you record the opening and the closing sounds. Then you can measure accurately the time. The program can be found here:
http://audacity.sourceforge.net/

Andrew
19-Mar-2010, 14:57
I have one of these too... they're branded "OMES"

sure, it looks like a simple device that someone who does electronics might knock up pretty cheaply at home but for most people getting all the parts and tools and then making one would be prohibitive so I think the asking price is actually very fair. I haven't used a soldering iron for over 20 years and I'd never finish the project!

overall, I'm glad I bought it. I've used it to check several old shutters and flagged one I wanted to mount an old barrel lens into as behaving very erratic so that one got sent off for service before I wasted any time/film shooting with it. Fortunately most of my shutters seem to be close enough to marked times that I won't worry about the errors.

I can now get an objective speed for my packard shutters and toy cameras etc but, for me, the main value has been measuring how consistently a shutter runs.

jwaddison
19-Mar-2010, 20:42
Some guy from another forum used this free audio recording software (I downloaded it, but have not used it). Wat you do is you record the opening and the closing sounds. Then you can measure accurately the time. The program can be found here:
http://audacity.sourceforge.net/

I downloaded this and tried it, and it seems to work ok for the slower speeds (1/15th sec to 1 sec), but the "start" and "finish" is too fuzzy to see for the faster speeds - possibly unless you know exactly what you're looking at, which I don't.

I wonder if it's reasonably safe to assume that if you're ok at the slower speeds the faster ones are probably ok?

Nathan Smith
20-Mar-2010, 07:37
I wonder if it's reasonably safe to assume that if you're ok at the slower speeds the faster ones are probably ok?

No, not a good assumption.

Sevo
20-Mar-2010, 08:30
I wonder if it's reasonably safe to assume that if you're ok at the slower speeds the faster ones are probably ok?

No - common modern shutters have three escapements and springs between which they switch at defined thresholds, even a perfectly timed range need not mean that the shutter is not outright broken in another. Besides, clumsy DIY repairs do mostly "correct" a flaw by introducing a second level of maladjustment. Usually, shutters dragging at slow speeds end up sprayed with grease, and will be too fast at mid-range speeds, only to slow down again at the fastest speed or two (where the grease acts as a viscosity brake).

ederphoto
21-Mar-2010, 07:09
They work .But you can make one for less than $40.00 and it is going to work in the same way .You can even one for $10.00 and use your computer to read the results through a sound card and it is guaranteed to work as a $1000.00 shutter tester !

Brian Ellis
21-Mar-2010, 07:51
The pictures look nice, the seller is reputable, the fact that others could make one for less is irrelevant since they haven't offered to make one for you, so if you want a shutter speed tester why not give it a try.

Dave Loftus
21-Mar-2010, 08:44
The Audacity software is good; however, I use it with an OPTICAL sensor that plugs into the microphone input. Built it for cheap from simple schematics. Shining a strong light source through the shutter, Audacity detects and displays a "sound" (actually a light) wave that corresponds to the shutter opening and closing. Circuitry resides in a little 35mm film canister with an external AA battery. I think the whole shebang cost me less than $10 and a little solder.

Arthur Nichols
21-Mar-2010, 08:49
before purchasing on the Omes testers I tried to use my sound card. I almost have it working. I can see a response on the editing program but I bought a stereo jack instead of mono and can't seem to get the wiring quite right. If some has done this can you please chime in and let me what I am doing wrong. I used this schematic.
http://www.nikonhs.org/tech_articles/stester.html

Ivan J. Eberle
22-Mar-2010, 05:55
You may not need any resistors in the cicuit. My 15" Mac Book Pro has an auto level detect on the
Line-In. My tester couldn't be simpler to build-- a very satisfying project.

Denis Pleic
22-Mar-2010, 06:24
I've had some DIY photo pages for ages now - among them plans for TWO shutter testers.

The first version is a design that I found on the net, but the original web site is long gone (was hosted on Geocities...).

The second version was invented by a friend, and does not need either a separate power source (no batteries), or a light source - it has a bright LED as light source , and everything is powered from USB computer port.
The friend who designed it does not speak English, but I got his permission to make the plans and design available for free to everyone :)

Anyway, HERE (http://www.hrtranslations.com/photo) you'll find both versions, plus some other stuff which might be of interest.

gevalia
22-Mar-2010, 07:04
Anyone try one of these? They look pretty good.
http://cgi.ebay.com/Shutter-Tester-for-Rangefinder-SLR-Leica-Canon-Nikon_W0QQitemZ170423507964QQcmdZViewItemQQptZFilm_Cameras?hash=item27ae085bfc

Paul Dixon sells testers on fleabay. You can contact him at pauldixon@cox.net. I'm not affiliated with him. His testers are the simple DIY testers but they are accurate when used with Audacity and cheap (for those of us that don't want to spend the time on the soldering). In the past I have sent a few to Carol so I used her notes to confirm. I burned quite a few sheets of film when I had the shutter tester in my drawer. My timings are all consistent so I'm in no rush to send them all to Carol.

And "sounds right" is meaningless.

John Hoang
22-Mar-2010, 08:27
Has anyone tried this? Easy and no soldering required.

http://decisivemomentum.blogspot.com/2008/07/using-dslr-as-shutter-tester.html

John MacManus
25-Mar-2010, 14:13
Yes John, I followed that fella's suggestions and used my Canon DSLR to test some focal plane shutters on Graflex cameras. Worked great after a bit of fiddling.

I had done some work on one of the shutters with a buddy's oscilloscope/photocell setup and the numbers agreed. I also used a Schneider lens in Copal shutter as proof of the method. So I am happy to proceed to test the next shutters that cross my path.

Go ahead and give it a try ... certainly easier than messing with Audacity which I hated ... good luck ... J

Arthur Nichols
25-Mar-2010, 14:54
I tried the Audacity method as well. It seems to work OK for slower shutter speeds like under 1/125. Anything over this it becomes hard to sort out the curve and tell when the shutter opens and closes. My computer has a 5 VDC output on microphone input. I just wired this through a phototransistor and it generally worked but as I said at the lower speeds. I tried messing around with resistors and capacitors like shown on the schematics all over the internet but it didn't make a difference. Unless some one can jump in and let me know I need to do get reliable shutter readings via my sound card I guess I will have to bite the bullet and buy the real thing.
Art

bobwysiwyg
25-Mar-2010, 18:59
I've used the Audacity method also. It seemed to work fine, and I thought up to about 1/250th on most of my cams (Pentax SV, Nikon FE/FM) and LF lens. However, I noticed that when I tried to use it on my Nikon F, it was very difficult to sort out the start and end. I'm wondering if it can't vary by camera shutter design and implementation also. Anyway, seemed good enough for gov't work.

Ivan J. Eberle
26-Mar-2010, 04:23
The Audacity method only works as well as your phototransistor and the selected sampling rate allow. I bought a fast-switching transistor (~10 microseconds and 10X the price of a Radio Shack one but still only $13).

For the money and the minimum of effort, this has to be one of the best hacks ever.

Arthur Nichols
26-Mar-2010, 05:43
where did you buy the fast switching phototransistor?

Tim Meisburger
26-Mar-2010, 10:09
Yes, I tried this, but could only get a reading at very slow speeds, Above about 1/20 second the wave form was unreadable, and I never was able to get the square wave shown on the website. Perhaps I had the wrong capacitor, photocell, or had not set up the program the way I should? Oh well...

harlekin
26-Mar-2010, 11:33
I just built and used a shutter tester of this sort. I was able to measure the 1/400 speed on my graphex shutter (which apparently a full stop slow, c'est la vie). With a bit of improvement to the design I'm sure it could measure a few stops faster fairly reliably.

My soundcard was supplying 2V on the ring, which I understand is likely through a 2k resistor internally. I used an NTE 3034A phototransistor that I bought at Fry's (NTE is one of the more common semiconductor suppliers for retail stores.) I hooked it up as a common emitter amplifier with a DC blocking capacitor to the connector tip. (power to the collector, collector to the cap to the output, emitter to ground.) I'd show a schematic, but I don't have a good way to draw it up at the moment. Use the smallest ceramic cap you can find (I think mine was a 1.5uF cap). At the faster shutter speeds I had to be careful where I measured from as the charging time of the cap was noticeable (about 1ms).

Using an external power source might be necessary to reduce the source impedance so that I can get a faster charge time on the cap. I could possibly try another configuration without a cap, but I really don't want DC coupling into my sound card. The sampling rate on the sound card is 44.1kHz, so if the circuit is good, the sound card should be able to easily resolve shutter speeds as fast as 1/2000.

Jack Dahlgren
26-Mar-2010, 11:36
I put together my own circuit for this and was working out a way to make a digital read-out, but the digital camera testing method is SOOOO simple that I quit. Just put the camera facing a well lit circuit and you can test all the shutter speeds really quickly AND get an idea of what the amount of variance really means.

I use older lenses and shutters so it is really useful to see the results of a slightly slower top speed on the image instead of just knowing that it is 0.0138 seconds slow.

rdenney
26-Apr-2010, 08:37
I bought one of the below testers that is made like the schematics we see:

Pre-made shutter tester from "Lurchrider" (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150437261687&ssPageName=ADME:X:RTQ:US:1123)

I plugged it into the mic input of an EMU external soundcard and recorded using Audacity (which is free). I turned the record level control all the way up.

When the diode triggers when light appears, the voltage output is a positive spike. When the light goes away, there is a negative spike. The spike on the graph comes (necessarily) after the change in light reaching the diode, so I just "selected" (in Audacity) from the leading edge of the first (positive) spike to the leading edge of the next (negative) spike. I was able to measure all the speeds of all my shutter easily.

My test technique was to remove the rear cell of the lens, hold the tester up against the rear of the shutter, centered as well as possible, set the aperture to wide open, and then hold the lens board/tester combination in my left hand. With my right hand, I started the record mode of Audacity, cocked the shutter, pointed it to an incandescent desk lamp, released the shutter, cocked and fired the shutter three more times, and then stopped the recording. All four firings easily fit in a 10-second window. Then, I ignore the first firing, and zoom into each of the remaining three. Once zoomed in, I select the sound file between the peaks as described above, and read the information line about the selection, which includes the elapsed time. I recorded that in a spreadsheet.

I set up the spreadsheet to average those three readings, and then provide an error in stops by taking the log of the ratio of the actual time and the nominal time and dividing that by the log of 2.

It took me three hours to test 8 lenses, including downloading and installing Audacity, building the spreadsheet, and conducting all the tests. Repeat tests will take only an hour at most.

I was able to test even 1/500 speeds with good reliability. My general result was that my Compurs were pretty good at the fast speeds and draggy at the slow speeds, while the Copals were pretty good at the slow speeds but optimistic at the fast speeds. The best shutters were within a quarter stop up and down the range of useful speeds, but none were perfect. I now keep the resulting table in my bag.

Yes, I could have built the tester for maybe half what this one cost, but I would have had to order the photo-transistor--Radio Shack only sells IR-sensitive photo-transistors in their typical floor plan. Buying it complete was worth it just for the time savings, and would be especially so for those who don't own soldering irons.

Rick "who'll start sending in the worst ones for a CLA" Denney

BetterSense
26-Apr-2010, 09:06
FYI, the radioshack IR sensor will work fine with a desk lamp or similar light source.

rdenney
26-Apr-2010, 09:29
FYI, the radioshack IR sensor will work fine with a desk lamp or similar light source.

Okay. Too bad Radio Shack doesn't provide any technical description of the device so that one buying it would be able to know that.

Anyway, sometimes I'm in the mood for a project and sometimes I just want it to work. This time, I just wanted it to work. <$40 requires no justification; >$100 for something like a Calumet tester does.

I found it easier to use than a Calumet tester, by the way. With that, even the pulsing of AC from an incandescent bulb caused problems, and I had to use a DC-power flashlight as the light source for that tester. It saved the step of measuring the pulses in Audacity, but required a trickier setup. I borrowed one once to test medium-format shutters some years ago.

Rick "thinking that mic input is a pretty useful general A/D sampler" Denney

BetterSense
26-Apr-2010, 09:46
Yep. Been there myself.

I've been thinking about using a microcontroller and LCD to make a field-usable shutter speed tester, but the computer-interfacing ones actually have the advantage that you can precisely pick out the beginning of the voltage spikes, and intelligently discard noise and other weird results. So I could make one, but it wouldn't be better than a sound-card one.

Bart B
7-Nov-2010, 05:40
I came up with my own shutter speed tester that measures what counts; to me, that is. Shutters are supposed to let light through them for a given amount of time. Leaf shutters inside lenses have a transit time between their closed and full-open positions. For a given shutter speed, I think a lens with a smaller f/stop will have a longer "open" time than what a larger f/stop has. So I wanted a method to show the actual amount of light that gets through the shutter during its cycle time. Here's what I came up with.

Most electric motors turn at about 1750 rpm. They'll make one turn in about 1/30th second. If you put a black round thing (pulley?) on it with a white spot at its edge then take a picture of it spinning, that spot will make a circular blur on the image plane while the shutter's open. Each end will have light fall off as the shutter opens and closes. To see exactly what your motor turns that pulley in 1/60th of a second, use a decent digital camera to take a picture of it. Here's what my pulley looks like; a reflective white square's at the edge spinning at about 1750 rpm using a digital SLR's speedlight:

http://farm2.static.flickr.com/1185/5154201190_5ff417b05d_m.jpg

Here's the pulley picture taken at 1/60th second with the same camera; note the grey blur starting at the top then ending about 162 degrees clockwise:

http://farm5.static.flickr.com/4149/5154201184_2841682eb5_m.jpg

The spot's arc should have been about 175 degrees at 1750 rpm. As the arc's only about 162 degrees, that translates to about 1890 rpm.

This is how I calibrated the motor speed using a very accurate 1/60th shutter. Comparing a test picture using the shutter under test to this one will show how accurate it is. A drill press spindle spinning at a lower speed will work for shutter speeds below 1/60 second. Plans are to get a really flat black paint (or something else) so there's better contrast between the white spot and the pulley.

I'm working on the setup to test my Graflex 1000 shutter. Plans are to use the DSLR to photograph the Super Speed Graphic's ground glass in a dark environment showing the bright-light illuminated reflector making traces. Grade school math can be used to determint acutal shutter speed by how many degrees rotation the spot has.

Comments, suggestions are welcomed.

Bart

Denis Pleic
7-Nov-2010, 06:32
Bart, this is a true and tested method :)

See HERE (https://ritdml.rit.edu/bitstream/handle/1850/1487/ADavidhazyReport03-30-2006.pdf).

Turntable, TV.. I've also seen a drum method, as used by late S.K. Grimes, see HERE (http://www.skgrimes.com/idcc/index.htm).

Jack Dahlgren
7-Nov-2010, 07:13
Bart, this is a true and tested method :)

See HERE (https://ritdml.rit.edu/bitstream/handle/1850/1487/ADavidhazyReport03-30-2006.pdf).

Turntable, TV.. I've also seen a drum method, as used by late S.K. Grimes, see HERE (http://www.skgrimes.com/idcc/index.htm).

What are these things called TV and Turntable?

Stick an LED on the end of that motor thing and it will show up better.

Bart B
7-Nov-2010, 07:24
Jack, a "turn table" is that thing your 90-inch HD television sits on so you can swivel it around to see it head-on from anywhere in your huge entertainment room. And "TV" stands for Terrific Vehicle; what I call my BMW Z3 coupe. (my left eye's winking.....) I, too, thought of an LED; I've got one on a quarter-sized key-fob flashlight that I could afix to the pulley. Then take pictures in a darkened room and that bright point of light will be great to use. That fob-LED laying on a phonograph turn table will be great for testing slow shutter speeds; plenty accurate, too.

Denis, thanks for the link showing other moving things photographed to measure shutter speeds. I'm not surprised someone else thought of this method. I like the idea about using a phono turntable for slower speeds; I'll use mine to do that; it's 3 speeds make it very useful. I got the idea of a pully on a motor from back in 1959 when I got my Nikon S3 rangefinder camera. Set up an HP oscilloscope to make a circle on the screen, then took pictures of it at different shutter speeds. The circle was only about 1/8th inch diameter on the slides so the focal plane shutter wouldn't effect the results too much.

Bart B
7-Nov-2010, 11:45
Seems I forgot something that may be crucial to the issue.

If Nikon's shutter electronics in their D40 is exact double/half from a given full stop setting starting from 1 second, setting the shutter to 1/60th would be 1/64 second. At 1750 rpm, that dot will travel about 164 degrees. Which now convinces me that my reasoning was a bit flawed before. It's probably the same thing as f/stops where only f/2, f/4, f/8.... and doubles thereafter are exact. Apertures of f/4.5, f/5.6, f/11, f/22.... are not exact, but just easy things to remember for settings inbetween the exact ones.

There's easily a 2 degree error in my measuring techniques for that arc of grey shown in the picture. It's a fluke that the difference I thought was caused by an outlet voltage to spec'd on the motor would cause the same error.

My reasoning's got a lot of scar tissue on it. It's been flawed many times over the years. What's another one or two...........

BetterSense
7-Nov-2010, 12:32
When I was writing the software for my light meter, I had to resist the urge to create a 'real' shutter speed scale that actually doubled at each setting, like

1 1/2 1/4 1/8 1/16 1/32 1/64 1/128 1/256 1/512 1/1024

Most cameras have scales that go like this

1 1/2 1/4 1/8 1/15 1/30 1/60 1/125 1/250 1/500 1/1000

Bowing to convention, I wasted memory on an entire array of unique shutter speeds just so that the numbers look normal. It's hard to know what digital-operating cameras do internally. I would imagine they use the top scale, since it's very close to conventional shutter speeds and much more efficient to implement in software.

I never understood why we buy 100 and 400 speed film but have to make do with 1/125 and 1/500 shutter speeds.

Bart B
7-Nov-2010, 12:58
It's hard to know what digital-operating cameras do internally. I would imagine they use the top scale, since it's very close to conventional shutter speeds and much more efficient to implement in software.
I'm sure digital controlled shutters do operate in exact double/halve increments. 'Tis easy with binary systems.

There's a bunch of numbering standards for several things; for example:

The original meter as defined by the French government was one ten-millionth of the distance from the equator to the center of Paris. It's changed a tiny bit over the years.

Circular mil, four standards from 1/6000th to 1/6400 thousandths of a circle.

Mile, US Navy radar range is 2000 yards per mile (at least it was when I served), statute mile's got 1760 yards and a nautical mile's about 2027 yards (larger in the southern hemisphere, smaller up north).

Then there's the Baker's Dozen.......

And in the computer age, the complete set of binary groups below that computer's "eat" at one time as explained by a former Univac engineer to me when I worked at Sperry Gyroscope:

Bit, a single unit
Snyff, 2 bits
Nybble, 4 bits
Byte, 8 bits
Chomp, 16 bits
Gobble, 32 bits.

acanalda
9-Nov-2010, 05:01
HI to all,

A couple of years ago I made my own shutter speed tester. It works perfectly and is very cheap and easy to do.

Following I enclose the links to the forum where you can find the information

http://www.l-camera-forum.com/leica-forum/leica-collectors-historica/74978-how-made-shutter-speed-tester-step.html

http://www.l-camera-forum.com/leica-forum/leica-collectors-historica/74984-how-use-shutter-speed-tester.html

If you need more information feel free to contact me.

Regards

Arturo

Dominique Cesari
9-Nov-2010, 07:03
The original meter as defined by the French government was one ten-millionth of the distance from the equator to the center of Paris. It's changed a tiny bit over the years.

As a French citizen, I must strongly deny that :)
We are somewhat self-satisfied, but the meter was one ten-millionth of the distance from the equator to the North pole.

Bart B
9-Nov-2010, 11:03
As a French citizen, I must strongly deny that :)
We are somewhat self-satisfied, but the metre was one ten-millionth of the distance from the equator to the North pole.Oops!!! I was weak in being right; that's better than being wrong. Checked my reference and sure enough, it's the North Pole that's ten million metres north of the equator.

That famous landmark at the center of Paris (48 51′ 12.24″ N, 2 20′ 55.68″ E) is about 5,432,060.353 metres north of the equator. To me, the French though in much larger, more worldly scales in establishing this great standard. The "yard" and "foot" originations were based on the dimensions of a couple of human body parts.

France; best place I saw there was the Palace of Versailles. Neat place, indeed.

Wally
25-Nov-2010, 01:58
Well, I haven't liked any of the shutter testers I've seen - they all have limitations that make them difficult if not impossible to use in the field.

So I made one that would be easy for me to use when I'm out trying to get a shot and want to know what compensation I need to use to cope with my old shutter's inaccuracy.

I decided that to be most useful it needed to meet these criteria:

It needed to fit in my pocket or my camera bag.

It needed to be battery operated so I could carry it into the field, and should be kind to the batteries.

It needed to show me the shutter speed in fractional and decimal formats: Fractional as in "1/xxx" where xxx might be 2.00 for a half second, and decimal so when I test the one second setting It's easy to read (1/0.96 for a slightly slow shutter is not intuitive).

It needed to "just work" - turn it on, set your lens over it, pointed at the sky, trip the shutter and get a reading.

I've got it working very well, and it meets the above criteria - It uses a little switching power supply to squeeze out dozens of hours of run time from a pair of AA batteries, and when it detects a measurable doze of light it toggles continuously between fractional and decimal representations with a 2-second pause between.

Here's a couple of pics of the prototype on the bench. I'm laying out a circuit board now so I can make a version to fit into a nice case.

Jack Dahlgren
25-Nov-2010, 10:03
Well, I haven't liked any of the shutter testers I've seen - they all have limitations that make them difficult if not impossible to use in the field.

So I made one that would be easy for me to use when I'm out trying to get a shot and want to know what compensation I need to use to cope with my old shutter's inaccuracy.

I decided that to be most useful it needed to meet these criteria:

It needed to fit in my pocket or my camera bag.

It needed to be battery operated so I could carry it into the field, and should be kind to the batteries.

It needed to show me the shutter speed in fractional and decimal formats: Fractional as in "1/xxx" where xxx might be 2.00 for a half second, and decimal so when I test the one second setting It's easy to read (1/0.96 for a slightly slow shutter is not intuitive).

It needed to "just work" - turn it on, set your lens over it, pointed at the sky, trip the shutter and get a reading.

I've got it working very well, and it meets the above criteria - It uses a little switching power supply to squeeze out dozens of hours of run time from a pair of AA batteries, and when it detects a measurable doze of light it toggles continuously between fractional and decimal representations with a 2-second pause between.

Here's a couple of pics of the prototype on the bench. I'm laying out a circuit board now so I can make a version to fit into a nice case.

Are you going to post the schematic and code?

Wally
25-Nov-2010, 10:44
Are you going to post the schematic and code?

When you post the the drum scans of your images. :p

I'm currently unemployed and am thinking of selling these to make a little income once I get them into a presentable form. If it helps me continue to be able to buy film, it's worth my effort.

I don't imagine there's a big market for the device, but if I make the most useful one out there and offer it at a reasonable price to users of no-longer-manufactured-and-slowly-aging shutters, it might sell.

But that's at least a couple of months away. I haven't even started laying out the board. I've just been coding and building the prototype, and have finished some in-the-workshop testing.

rdenney
25-Nov-2010, 14:06
...and offer it at a reasonable price...

If you get this part right, I'll buy one. For me, that would be in the hundred-buck range. Can you make them cheaply enough to fit that price?

Rick "asking the fundamental question of any business plan" Denney

Wally
25-Nov-2010, 17:12
If you get this part right, I'll buy one. For me, that would be in the hundred-buck range. Can you make them cheaply enough to fit that price?

Rick "asking the fundamental question of any business plan" Denney

That's my target: under a hundred. Then it makes sense to have one.


// Wally

Michael Cienfuegos
26-Nov-2010, 09:29
That's my target: under a hundred. Then it makes sense to have one.


// Wally

Sounds good to me, I would like one. :) please.

Wally
26-Nov-2010, 09:39
I'll start a list. :D

John MacManus
26-Nov-2010, 13:47
I'd like one too please Wally.

ASAP :) ... thanks ... J

Acheron Photography
26-Nov-2010, 14:22
Me too please.

Thanks

David

GeorgesGiralt
27-Nov-2010, 10:07
Hello Wally,
Add me to the customer list....
Can't wait !

Wally
27-Nov-2010, 10:10
You're in!


// Wally

Ron McElroy
29-Nov-2010, 17:48
In the under $100 range sounds great. Put my name on the list as well.

Joe Osten
30-Nov-2010, 01:58
Hello Wally,
Please put me on the list for a shutter speed tester. Please note that I am located in the UK and France.
Best regards,
Joe Osten

Wally
30-Nov-2010, 10:21
I've got seven people on the list as of this morning.

I've ordered the parts* to make twenty units, so there should be enough even if some more people sign up.


// Wally

*I'm still laying out the board, so it's not ordered yet. I expect to have it submitted for fabrication by next Monday.

Roboflick
1-Dec-2010, 14:16
Add me on to the list as well please
Thanks
Nik

Wally
1-Dec-2010, 14:33
There are now eleven people on the list.

I finished laying out the board this morning, and will be getting a quote from the board makers.

I'm planning on using a 49mm rubber lens hood to nestle the back element close to the sensor to keep stray light out.

// Wally

P-Fitzs
2-Dec-2010, 06:54
I am interested in one of these also.

imagedowser
2-Dec-2010, 08:10
"Way Beyond Monochrome" has a section on using Audacity to make a shutter tester, page 470 in the second edition.

evan clarke
2-Dec-2010, 08:36
I use "oscilloscope app" on my iPhone....it really works..EC

rdenney
2-Dec-2010, 11:06
"Way Beyond Monochrome" has a section on using Audacity to make a shutter tester, page 470 in the second edition.

We've explored these options in considerable detail in past threads. Suffice to say, sound cards filter DC which affects the way in which they measure the response of a photo-transistor. It's fine for slower speeds, but gets dicey for faster speeds.

I've built several of these, up to and including using an oscilloscope to measure the output instead of a sound card. I longed for something more self-contained and convenient at a reasonable price. That's the direction Wally is going.

Here's one of those discussions:

http://www.largeformatphotography.info/forum/showthread.php?t=62916

Rick "been there; done that" Denney

ac12
4-Dec-2010, 20:12
If the price is something that I can afford, I would be interested.

Wally
4-Dec-2010, 21:18
If the price is something that I can afford, I would be interested.

I'm shooting for under $100.

The board is routed. I'm submitting it for a quote on Monday.

Wally
7-Dec-2010, 18:22
I'm shooting for under $100.

The board is routed. I'm submitting it for a quote on Monday.

Well, a day late, but I uploaded the artwork and am waiting for a quote for 24 boards!

Wally
7-Jan-2011, 21:40
My first shutter speed tester is up and running!

I'm now just waiting for the enclosures to come back from the machinist.

I've got the parts to make a dozen, all of which are spoken for (thanks, everybody)!


// Wally

ac12
8-Jan-2011, 15:38
Oh wow, surface mount components.
Man that stuff is too small for me to solder. Glad you know how to do it.

Wally
8-Jan-2011, 17:42
Oh wow, surface mount components.
Man that stuff is too small for me to solder. Glad you know how to do it.
The voltage regulator chip (second black component to the left of the power switch) is very difficult.

It's 2mm x2mm and has six pads around the edge with zero lead length, and one ground pad in the center. The six are a quarter of a millimeter wide and spaced half a millimeter apart. Getting the solder pad stencil lined up is very hard - there was lots of 'redo' on the first three. With practice it's getting easier.

Leigh
8-Jan-2011, 18:14
Surface mount?

Definitely auto-place with adhesive and IR reflow. Would never attempt hand soldering.

Looks like a nice product.

Specs?

- Leigh

BetterSense
8-Jan-2011, 18:32
The voltage regulator chip (second black component to the left of the power switch) is very difficult.


I tried to use some MSOP buck/boost converter chips for my homemade lightmeters and gave up trying to solder them. I ended up buing some on a breakout board from sparkfun. The proliferation of SMD components is a real bummer for the hobbyist.

Wally
8-Jan-2011, 20:03
Surface mount?

Definitely auto-place with adhesive and IR reflow. Would never attempt hand soldering.

Looks like a nice product.

Specs?

- Leigh

I don't hand-solder the DFN component. I bought an IR convection toaster oven from Target and a ramping PID controller from eBay and use that combo with Kester's recommended temp/time profile. I use a stencil and a very nice nickel-plated squeegee to apply the solder paste.

I have been hand-solder the through-hole, SO-8, TQFN-32 and 0805 passives, but will probably try doing all in the toaster oven on the next batch.

The shutter timer uses a PIN photodiode in photoconductive mode to get fast rise times.

The micro uses internal clocking at 1MHz. It uses the 32.768KHz crystal and it's 8-bit timer to calibrate the internal oscillator at program start-up.

The device will measure the number of 1MHz clock ticks seen by the 16-bit timer, keeping track of overflows, and then scale the output to display the decimal and fractional measure of the shutter time.

If, for example, the user places the lens over the unit, sets it's shutter to 1/8th second and trips the shutter, the device may display 1/7.453 for two seconds, then 0.13417 for two seconds, then repeat, until a new burst of light is detected*.

If the device sees one or more seconds of light, it displays the number of seconds and the fractional part for two seconds, then the number of seconds and decimal part for two seconds and repeats.

*if the shutter's a tiny bit slow

Leigh
8-Jan-2011, 20:22
Hi Wally,

The toaster oven is a neat idea. I just send my stuff to a fab house and it comes back done.

I'm still in the through-hole world; easier to do reworks, repairs, and mods compared with SMD.

Sounds like a nice design.

I've done some similar projects over the years but never thought to include the fractional display. Nice feature.

Good luck with the project. I'll be interested in seeing the final product.

Thanks.

- Leigh

evan clarke
9-Jan-2011, 06:19
The nice thing about the oscilliscope app on my phone is that I can check a shutter anywhere in the wild under any conditions. Shutters work differently on the North Shore of Lake Superior in -30F weather than they do in your nice, warm darkroom!!

Michael Cienfuegos
15-Feb-2011, 12:27
I have Wally's Shutter Speed Tester. It works! I have only used it with my Speed Graphics (Pacemaker and Pre-Anny 4x5) and my 2x3 Graflex RB Series B. Needless to say, the focal plane shutters are way off on these old cameras. The pacemaker FP Shutter: 1/30 is actually 1/13, 1/50 is 1/35, 1/125 is 1/114 (not too bad), 1/250 is 1/127; 1/500 is 1/328 and 1/1000 is a whopping 1/358. I will try and do a better sampling of shutter speeds to see how much deviation in each setting.

Wally
15-Feb-2011, 13:40
Please bear in mind that my shutter tester isn't designed to give accurate readings for focal plane shutters. It was designed to measure leaf shutters.

engl
15-Feb-2011, 15:39
Am I missing something, or is not all the devices based on photo-transistors going to report inaccurately at high shutter speeds with a leaf shutter?

The blades do not move instantly. The center opens first, then a number of lines (depending on the number of blades) extending from the center to the edges. These areas then extend until they meet and the shutter is fully opened. At the highest speeds, the shutter starts closing right after it has opened, so the shutter is going to spend a fair part of the full cycle in one of these "half-opened" states.

Depending on placement of the light source and photo-transistor, you could get different measurements even with a perfectly consistent shutter. There is no easily found spot giving representative measurements. The center is always open quickest (giving the impression of a slow shutter, since it is letting though light for a longer time, at only this small part). Measuring at a distance from the center gives a random reading, depending on if the position happens to fall on one of the "lines" that open quickly, or the parts that open later.

The selected aperture will of course also affect how much being "half-opened" affects the effective shutter speed. It is worst at wide open, and at F64 the entire image is coming though the nearly instantly opening center. If 1/500 is used I'm going to guess the lens is not stopped down a lot, so bigger apertures probably are the most relevant to measure at high speeds.

The best way to get an accurate measurement for high shutter speeds should be to measure light at the image plane, comparing brightness to a DSLR shutter, modern electronic focal plane shutters are very accurate. Different aperture settings will give different effective shutter speeds with a leaf shutter, so many measurements are needed.

Jack Dahlgren
15-Feb-2011, 16:01
Am I missing something, or is not all the devices based on photo-transistors going to report inaccurately at high shutter speeds with a leaf shutter?

The blades do not move instantly. The center opens first, then a number of lines (depending on the number of blades) extending from the center to the edges. These areas then extend until they meet and the shutter is fully opened. At the highest speeds, the shutter starts closing right after it has opened, so the shutter is going to spend a fair part of the full cycle in one of these "half-opened" states.

Depending on placement of the light source and photo-transistor, you could get different measurements even with a perfectly consistent shutter. There is no easily found spot giving representative measurements. The center is always open quickest (giving the impression of a slow shutter, since it is letting though light for a longer time, at only this small part). Measuring at a distance from the center gives a random reading, depending on if the position happens to fall on one of the "lines" that open quickly, or the parts that open later.

The selected aperture will of course also affect how much being "half-opened" affects the effective shutter speed. It is worst at wide open, and at F64 the entire image is coming though the nearly instantly opening center. If 1/500 is used I'm going to guess the lens is not stopped down a lot, so bigger apertures probably are the most relevant to measure at high speeds.

The best way to get an accurate measurement for high shutter speeds should be to measure light at the image plane, comparing brightness to a DSLR shutter, modern electronic focal plane shutters are very accurate. Different aperture settings will give different effective shutter speeds with a leaf shutter, so many measurements are needed.

Engl,

I think you are partly right. The part that is wrong are the "lines" that you talk about. If what you are saying is true, then a high speed shot of an evenly illuminated surface would show these lines. Remember that it is a lens and aperture so the aperture does not cast a shadow in the normal way. However, the amount of light passing through it does vary over time, so the ramp up and down is a greater portion of a short exposure compared to a long exposure - just as you say.

engl
16-Feb-2011, 03:23
Engl,

I think you are partly right. The part that is wrong are the "lines" that you talk about. If what you are saying is true, then a high speed shot of an evenly illuminated surface would show these lines. Remember that it is a lens and aperture so the aperture does not cast a shadow in the normal way. However, the amount of light passing through it does vary over time, so the ramp up and down is a greater portion of a short exposure compared to a long exposure - just as you say.

I'm not quite following. As you say, the shutter blades act as an aperture, and thus will not cast a shadow, just like a "star filter" will not affect in-focus areas. Why would a high speed shot of an evenly illuminated surface show these lines?

In out-of-focus areas however, the shape of the aperture will show, and the "lines" I talk about are visible. You can see them here in a thread I made last year:
http://www.largeformatphotography.info/forum/showthread.php?t=62197

Notice also the reply by Struan Gray, showing the exact same pattern in a real shot OOF highlight.

The reason is that leaf shutter blades do not open and close in the same way aperture blades do, which keep a nearly circular opening. It is more of a star shaped opening, you can see it pretty well in this video of a slowly closing leaf shutter:
http://www.youtube.com/watch?v=-oKydf72Jik

Imagine measuring the shutter in the video. If you are measuring at only one spot, you'd get radically different speeds depending on where you measure. The center is open very long, and the "lines" are open much longer than some other areas at the same distance from the center. You'd have the same issue even if the shutter was moving at the correct full speed.

Sevo
16-Feb-2011, 03:49
For leaf shutter speeds which are fast relative to the actual shutter travel, photocell switches are problematic. It is possible to set their threshold so that they give accurate readings for any shutter time given a constant shutter travel speed (real world shutters however tend to have two or three travel speeds), defined constant illumination and diffuse metering across the entire shutter. But these are rather unusual requirements, none of the small shutter timers are equipped with a diffuser, and a constant DC powered high powered light source is not exactly a household item either (only LF studios operating scan backs will sometimes own HMI cine lights). Improvising and calibrating a test rig will not be not easy.

Another (for many cheap and trivial, as the equipment often is already be at hand) way to do accurate tests for short times would be to use a TTL flash meter probe - by making believe that constant lighting is flash this will actually do a cumulative reading of the light passing through the lens and shutter. If the transmission of the lens is known and the aperture is accurate this can be as accurate as the meter allows...

engl
16-Feb-2011, 05:37
I'm not quite following. As you say, the shutter blades act as an aperture, and thus will not cast a shadow, just like a "star filter" will not affect in-focus areas.

It was too late to edit, I realized I made a mistake here. I do not mean a "star filter" but rather shaped apertures, this kind of stuff:
http://www.diyphotography.net/diy_create_your_own_bokeh

rdenney
16-Feb-2011, 06:19
The shaped aspect of a leaf shutter as it opens isn't really that important. What is important is the integrated quantity of light.

When the shutter first cracks open, it will soon pass through the equivalent of f/128. A little later, it will pass through the equivalent of f/64. Then, it will pass through f/45, and on up to the taking aperture. All this takes time.

But I don't think it's particularly important for most of us. For one thing, most large-format photographers use apertures of f/22 of f/32. The time required for the edge of the shutter leaves to pass the edge of the aperture blades and no longer be relevant is only a fraction of the time required to open fully.

For large shutters where the blades might move slowly, one might have to remove cells and place the sensor perhaps halfway between the center of the shutter opening and the edge of the maximum aperture, if the desire is to ensure accuracy at wide apertures. Yet we use large shutters all the time over the full range of set apertures and never really worry much about the fact that the shutter opening and closing time affects small apertures differently.

Another point is that these aren't clocks, where we are seeking accuracy on the order of parts per million. The claimed accuracy of mechanical shutters is no better than +/- 20-30 percent in any case. With most of our shutters, we are trying to find the ones that are stops off, not fractions of a stop.

There is no reason why Wally's tester should not work on a focal-plane shutter if it is placed close to the shutter curtains and if collimated light is used. When mine arrives, I'll test that theory with the electronically regulated focal-plane shutter in my Pentax 6x7, which I have had professionally tested and which was found to be extremely accurate.

A bigger issue with phototransistors is their response profile, but I suspect Wally has dealt with that issue. In fact, are you even using a phototransistor, Wally? When we discussed this once before, we found a range of devices that can work faster. That discussion also revealed the flaw of using a sound card with phototransistors, which was a separate and much worse problem. Sound cards are filtered to prevent DC, so we are in many ways seeing the response curve of the capacitor used to do the filtering. I tested that line of thinking using an oscilloscope.

The trick with all these types of testers is to calibrate the light source to just exceed the measurement threshold of the system. This was a key feature in the instructions that came along with the Calumet tester, which I have demonstrated to my own satisfaction works fine when used properly, and which is similarly designed to what Wally has constructed.

Professional testers for focal-plane shutters measure the speed of each curtain. That's way beyond what Wally was attempting (in complexity and in dollars).

Rick "test technique is important, too" Denney

Wally
16-Feb-2011, 09:33
I've been busy scanning transparencies from my trip up Big Sur (amazing weather this last week!) and I see I missed some good conversation.

I've never considered the time it takes for a leaf shutter to open or close. After reading Rick's reply, I think I will continue to ignore it.

I use a PIN photodiode, operated in photoconductive mode for speed*. It's DC coupled to a very low input bias current OP AMP used as a transimpedance amplifier, so it's also good for multi-second measurements (the display will show, for example, "2 1/2.101" for a nearly two and a half second shutter open time (I've used the shutter timer to practice tripping the shutter on bulb for the right length of time).

I don't try to measure photon quantity, just duration. For the purposes of us large format people that take our pictures outdoors, with regular film, I can't imagine being concerned about the time-to-open (or time-to-close which can be different). The output of the amplifier is fed into a comparator, where it's compared to a threshold that's fixed at being somewhat above the output when the sensor's dark.

Sometimes in these circuits one must worry about rise/fall time. It wouldn't do if the sensor can respond fast enough but the signal gets slowed by it's amplifier. The op amp used has a slew rate of about .5 volts per microsecond, and the circuit operates on 4 volts** so it has a two microsecond rise/fall time. To put this in perspective, the 1/500th setting represents two miliseconds, a factor of 1000.

I run the micro at 1MHz from it's internal oscillator, which I calibrate each time the device is turned on using a 32.768Hz crystal. This gives the device an accuracy of +-30ppm, well more than enough to tell you whether your exposure will be a third of a stop off. Operating at 1MHz minimizes power consumption of the micro.


// Wally

*as opposed to photovoltaic mode which, while providing less noisy and wider dynamic range light measurement, is slower in response, as it would have to come up with the current to overcome the capacitance at it's P/N junction.

**by way of a small boost regulator: The little device will continue to produce that 4 volts even when the two AA batteries have been drained to 0.8 volts each!

Michael Cienfuegos
16-Feb-2011, 13:30
Another point is that these aren't clocks, where we are seeking accuracy on the order of parts per million. The claimed accuracy of mechanical shutters is no better than +/- 20-30 percent in any case. With most of our shutters, we are trying to find the ones that are stops off, not fractions of a stop.

There is no reason why Wally's tester should not work on a focal-plane shutter if it is placed close to the shutter curtains and if collimated light is used. When mine arrives, I'll test that theory with the electronically regulated focal-plane shutter in my Pentax 6x7, which I have had professionally tested and which was found to be extremely accurate.

The trick with all these types of testers is to calibrate the light source to just exceed the measurement threshold of the system. This was a key feature in the instructions that came along with the Calumet tester, which I have demonstrated to my own satisfaction works fine when used properly, and which is similarly designed to what Wally has constructed.

Professional testers for focal-plane shutters measure the speed of each curtain. That's way beyond what Wally was attempting (in complexity and in dollars).

Rick "test technique is important, too" Denney

I guess that just setting my camera on top of the tester, placing a bright light over the lens and firing away would not be considered good "test technique" ?I knew that my old shutters were probably off. I have yet to check the shutters on my 1930's era Pre-Anny Speed or equally old Graflex SLR. At least I now have a ball park figure and I can hopefully meter my exposures with a little more accuracy. :p

m

Roboflick
25-Mar-2011, 13:12
My shutter tester arrived and works well. My 50 year old stereo realist is spot on at 1/100. I shoot it most often with velvia at 1/100 and f16 so this was good to confirm. The other speeds are all really close as well, except 1/200 which was 1/125. Not bad!
I also tested a contax iiia that i picked up with Opton sonnar lens for 100 dollars at a local camera shop. Those speeds were way off. The lens is really nice though. Now to test some large format shutters...
Thanks Wally!

JoeV
25-Mar-2011, 16:15
Those of you inclined to tinker in the shop, and who have access to an oscilloscope, may find it interesting that a clear-package diode will also exhibit photo-electric sensitivity. I wired up a simple circuit using a resistor, battery, diode and capacitor, and was able to time my shutters using an oscilloscope probe connected across the diode in DC coupling mode.

Of course, this setup isn't as convenient as a commercially built tester, but the price was right (free; I already had the parts on hand).

~Joe

Wally
25-Mar-2011, 21:00
This was discussed earlier in this thread and elsewhere (http://www.largeformatphotography.info/forum/showthread.php?t=62916). Some links were posted with schematics.

It's a great bargain: For only $5. in parts (except a scope or soundcard), it's something everyone can afford and it does work well enough to be very useful.

My initial shutter tester was the same circuit as yours. I noticed it had slow rise and fall times when I tried to test the faster shutter speeds, so I had to be careful how I interpreted their measurements.


// Wally

Chilidog
5-Apr-2011, 13:03
This was discussed earlier in this thread and elsewhere (http://www.largeformatphotography.info/forum/showthread.php?t=62916). Some links were posted with schematics.

It's a great bargain: For only $5. in parts (except a scope or soundcard), it's something everyone can afford and it does work well enough to be very useful.

My initial shutter tester was the same circuit as yours. I noticed it had slow rise and fall times when I tried to test the faster shutter speeds, so I had to be careful how I interpreted their measurements.


// Wally

there are a bunch of different links. Which ones?

OK, how about a simple, step by step explanation ala "shutter speed tester building for dummies."



Some of us are barely able to figure out which end of the soldering iron to hold.

Leigh
5-Apr-2011, 13:10
Some of us are barely able to figure out which end of the sldering iron to hold.
If it's plugged in, you'll figure it out. ;) :eek:

- Leigh

P-Fitzs
2-Jun-2011, 07:08
I received my shutter tester from Wally a few days ago and it works great.

Asher Kelman
28-Jun-2011, 10:38
Wally,

I'm interested too. Sending a PM!

Asher

parrotcam
11-Sep-2011, 08:51
Wally,
What is the current status of you tester offering?
Thanks,
Kurt

Wally
11-Sep-2011, 12:49
Wally,
What is the current status of you tester offering?
Thanks,
Kurt

It's been three months since I had the time to make a couple.

I had a bit of trouble with the voltage regulator with the initial run (if you put the batteries in backwards, the chip burns up as soon as the switch is turned on) and a new design using a different regulator didn't work - either they sent me a batch of bad chips or there's something wrong with my power supply design that I just can't see.

I've got cases and parts for another twenty units (going back to a previous board layout that uses the original regulator, but with a protection diode) but haven't got up the funds for a run of circuit boards using a new design with the old regulator and diode protection, and haven't had the time to make the changes to the layout in the CAD program.

Since I'm finding it so slow, the source (gcc for ATMega88) and schematics on my web site in the coming days.