What is you opinion of this shutter tester?

[noacronym]

Another thread about a shutter tester gave me cause to just browse EBAY for testers. I glommed onto this. Any opinions?
http://www.ebay.com/itm/Camera-shut...526?pt=LH_DefaultDomain_0&hash=item230a1554f6

 

[E. von Hoegh]

My opinion? Low. Very low. It doesn't measure how long the blades/curtains are actually open, it just displays the sounds the shutter makes and you guess what sound represents opening, and what sound represents closing.
I use a phototransistor and a dual trace scope, this actually tells me how long light is coming through the shutter.

 

[noacronym]

My opinion? Low. Very low. It doesn't measure how long the blades/curtains are actually open, it just displays the sounds the shutter makes and you guess what sound represents opening, and what sound represents closing.
I use a phototransistor and a dual trace scope, this actually tells me how long light is coming through the shutter.

Mr von Hoeugh I would be interested in your technique. I have a Tek 2335 scope, which would more than fit the job. My opinion of the tester mentioned wasn't much either. What did you do''fabricate a plate to put on the film rails with 2 phtotransistors, one at the left of the film gate and 1 on the right? What is your opinion of the mentioned tester on an iris shutter?

 

[noacronym]

It occurred to me some time after the above post that you would probably need a later model scope capable of re-playing a trace.

 

[bascom49]

The tester does not measure or record the sound of the shutter. It records the amount of time that the shutter is open.
When the shutter opens the light beam strikes a photoresistor. The circuit creates a signal that is recorded in time.
When the shutter closes and breaks the light beam the circuit creates a second signal that is recorded in time.
The time between signals is measured, that is the shutter speed as measured.

 

[rawhead]

The tester does not measure or record the sound of the shutter. It records the amount of time that the shutter is open.
When the shutter opens the light beam strikes a photoresistor. The circuit creates a signal that is recorded in time.
When the shutter closes and breaks the light beam the circuit creates a second signal that is recorded in time.
The time between signals is measured, that is the shutter speed as measured.

This is correct. I have the same tester from the same seller, and it works quite well up to 1/250. 1/500 is pushing it IMHO, as the waveform at that resolution is quite crowded so it's difficult to gage which curves correspond to the two events (shutter open and shutter close).

 

[E. von Hoegh]

The tester does not measure or record the sound of the shutter. It records the amount of time that the shutter is open.
When the shutter opens the light beam strikes a photoresistor. The circuit creates a signal that is recorded in time.
When the shutter closes and breaks the light beam the circuit creates a second signal that is recorded in time.
The time between signals is measured, that is the shutter speed as measured.

From the ad, no mention of anything to do with light:

"No battery and no maintenance needed! The tester works just like an electret microphone (a microphone that does not need a power supply). I have not heard of any PC sound cards that don't support electret microphones but you should still check if your sound card does"

 

[E. von Hoegh]

Mr von Hoeugh I would be interested in your technique. I have a Tek 2335 scope, which would more than fit the job. My opinion of the tester mentioned wasn't much either. What did you do''fabricate a plate to put on the film rails with 2 phtotransistors, one at the left of the film gate and 1 on the right? What is your opinion of the mentioned tester on an iris shutter?

The phototransistor is biased so it's just below the threshold of conducting, and it's masked so there's about a .025" slit (parallel to the curtain edges) for light to get to it. I place the gizmo just behind the shutter and trip the shutter. This gives a somewhat square wave on the scope, it's easy to read due to the persistence of the phosphors. Just calibrate the timebase for whatever speed(s) you're measuring, I use WWV as a standard. On a 35mm shutter, you can move the cell from left to right to measure the slit uniformity.

I wouldn't waste my time with that shutter tester on anything more sophisticated than a Packard.

 

[E. von Hoegh]

It occurred to me some time after the above post that you would probably need a later model scope capable of re-playing a trace.

I use a Tektronix 547 from the late 60s. A storage scope would be handy but not crucial.

 

[Usagi]

There's lot of DIY instructions for shutter testers like that one. I have built one simple. Works accurate enough for me and for a price. Better than recording a shutter's sound.


With a software like Audacity it's easy to measure how long shutter has been open.


Examples:

http://www.baytan.org/prak/shutter.html

Dead Link Removed



I would not fine tune shutter with testers like these, but they're easy for checking if speed are within ballbark.


ps. No laser pointer required, bright led flash light is good enough.

 

[noacronym]

The phototransistor is biased so it's just below the threshold of conducting, and it's masked so there's about a .025" slit (parallel to the curtain edges) for light to get to it. I place the gizmo just behind the shutter and trip the shutter. This gives a somewhat square wave on the scope, it's easy to read due to the persistence of the phosphors. Just calibrate the timebase for whatever speed(s) you're measuring, I use WWV as a standard. On a 35mm shutter, you can move the cell from left to right to measure the slit uniformity.

I wouldn't waste my time with that shutter tester on anything more sophisticated than a Packard.

Well that counts me out. I got rid of both my Hammarlund HQ180's. All I have is my Hammarlund HQ110, ham band only. So no WWV for me. This house is just too small for all my gadgets.

 

[Chan Tran]

Well that counts me out. I got rid of both my Hammarlund HQ180's. All I have is my Hammarlund HQ110, ham band only. So no WWV for me. This house is just too small for all my gadgets.

I also use a scope. Analog scope works fine although sometimes I borrow the digital scope from work and it's nice. I use a fiber optic based opposed sensor. The response time for the sensor is 50 microsecond so there is a limitation of high shutter speed.

 

[bascom49]

From the ad, no mention of anything to do with light:

"No battery and no maintenance needed! The tester works just like an electret microphone (a microphone that does not need a power supply). I have not heard of any PC sound cards that don't support electret microphones but you should still check if your sound card does"

The shiny thing in the middle of the black box in the photo is the photoresistor. You place your lens mount down on top of the black box and shine a light source through the lens, plug the cable into your sound card, start the recording software and trip the shutter.

The ad does mention a light source :

This tester is the result of thousands of tests with a lot of setups and light sources. You can find a thread on the Manual Focus Lenses forum ( link ) where I give a lot of details about the tester and explain why it is so cheap. Some users posted positive reviews. By posting this link I am NOT encouraging or implying bids outside eBay!

If you follow the link : http://forum.mflenses.com/shutter-tester-for-shutter-speed-up-to-1-1000th-14-99-t28474.html
you will see this post :

ludoo wrote:
An electret microphone means you are measuring sound, not light?


Hello, ludoo!
I said that it works like an electret microphone. I did not say it is an electret microphone. I was saying that you don't need a power supply to use it just like you don't need a power supply to use an electret microphone. The tester is measuring light!

Cheers!

 

[rawhead]

I don't get it. I comment that I have the same product and confirm that it's measuring light, not sound, and it just gets glossed over? LOL.

 

[noacronym]

I don't get it. I comment that I have the same product and confirm that it's measuring light, not sound, and it just gets glossed over? LOL.

I rather well thought it used light. I've done some study on FP shutter testers, and it seems the best design has 2 cells--1 on left and 1 on right.

 

[rawhead]

I rather well thought it used light. I've done some study on FP shutter testers, and it seems the best design has 2 cells--1 on left and 1 on right.

True, and the guy that makes those Ebay ones talks about that in the MFlenses thread linked above.

It's a $15 "tester", it's not going to give you the precision you need to fine-tune the shutter mechanism, check for uneven exposures, shutter bounce, etc. But it's been useful for me when I sell cameras on Ebay, etc., where I know I don't have weird issue like the above, but I'm not sure how accurate the shutters are, and for that one purpose only (i.e., measuring for how long light is allowed to pass through the shutter mechanism wherever you place the sensor), this tester is a-ok

 

[bascom49]

I don't get it. I comment that I have the same product and confirm that it's measuring light, not sound, and it just gets glossed over? LOL.

Who knows. At any rate I spent a rainy Saturday making a trip to radio shack and putting one together from a circuit diagram I found on line. Great fun and proved accurate using my Nikon F100 and several of my Nikon primes as a base line.

 

[rawhead]

Who knows. At any rate I spent a rainy Saturday making a trip to radio shack and putting one together from a circuit diagram I found on line. Great fun and proved accurate using my Nikon F100 and several of my Nikon primes as a base line.

Bravo

 

[noacronym]

Who knows. At any rate I spent a rainy Saturday making a trip to radio shack and putting one together from a circuit diagram I found on line. Great fun and proved accurate using my Nikon F100 and several of my Nikon primes as a base line.

Now RS only stocks infrared photo transistors and resistors.

 

[Andrew K]

guys - remember one thing.

Any simple shutter tested will only measure the elapsed time of a shutter, which is fine for leaf shutters, or to check the exposure a focal plane shutter is giving at the point where the tester cell is fitted in the camera plane.

It won't tell you 1st and 2nd curtain speeds, or whether a shutter is capping - for that you need a far more advanced shutter tester...

However if all you want is a time, then these testers seem to work well, based on the couple I've played with over the years..

cheers

Andrew (former Camera Technician with Canon Australia)

 

[Chan Tran]

Who knows. At any rate I spent a rainy Saturday making a trip to radio shack and putting one together from a circuit diagram I found on line. Great fun and proved accurate using my Nikon F100 and several of my Nikon primes as a base line.

If you could fire the shutter of your F100 show me how as I could not fire the shutter of my F5 with the back opened so I never could test the shutter of my F5.

 

[benjiboy]

Shutter testers are devices for increasing photographers sense of insecurity, because if they are inaccurate what are you going to do about it ?, if I suspect they are out I get mine tested by a professional and have him adjust them if neccesary.

 

[Ed Bray]

Shutter testers are devices for increasing photographers sense of insecurity, because if they are inaccurate what are you going to do about it ?, if I suspect they are out I get mine tested by a professional and have him adjust them if neccesary.

I have one of the cable testers shown, I made a small box for my Technika lensboards to sit in with the receiver at one end and an LED Maglite at the other, I tested all of my LF lenses and discovered that all my newer Copal shutters were accurate and repeatable up to 1/60, then there was a 1/3rd stop overexposure at 1/125 and at 1/250 and 1 stop at 1/400, in fact the graphs for1/250th and 1/400th were almost the same.
Unfortunately my Synchro Compurs and my Older Copal 3 did not do so well with some quite different times than expected across the range of speeds, what this did show though was the results were pretty repeatable. So for all the speeds that were incorrect I have marked the required compensation on the lensboards so as to give me a fighting chance when exposing the film

 

[AgX]

guys - remember one thing.

Any simple shutter tested will only measure the elapsed time of a shutter, which is fine for leaf shutters, or to check the exposure a focal plane shutter is giving at the point where the tester cell is fitted in the camera plane.

It won't tell you 1st and 2nd curtain speeds, or whether a shutter is capping - for that you need a far more advanced shutter tester...

However if all you want is a time, then these testers seem to work well, based on the couple I've played with over the years..

cheers

Andrew (former Camera Technician with Canon Australia)

Well, one might position the sensor at different points behind the focal plane and by this control variation in exposure time over the full-frame area.

 

[AgX]

True, and the guy that makes those Ebay ones talks about that in the MFlenses thread linked above.

That guy is a member at Apug (vfmoto) and once started a thread on these shutter-speed meters.

(there was a url link here which no longer exists)