Measuring shutter speed accuracy

Joao

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Hello
I am looking for sugestions concerning a reliable device for accurately measuring shutter speeds in film cameras. I am interested in something that
1. Measures light – I don’t want anything measuring sound
2. Can be used with both leaf shutters and focal plane shutters
3. Is easy to use and ready to use – I am not so skilled to build one myself
4. Can be used with a desktop/laptop computer (I do not intend to carry the device when I am out to shoot)
I have seen some models advertised but before I make a decision I would like to know practical experiences from members of RFF.
I remember seeing a thread on this topic in the past, but I was not able to find it...
Thank you in advance for your input
Regards
Joao
 
Do a google search on using your TV. The TV (like fluorescent light bulbs) oscillates too fast for the eye to see. But when you take a picture of the screen you'll see slightly diagonal bands on the screen. By counting the number of lines you can calculate the speed. Then again Calumet used to make a less than $100 USD shutter speed tester. I have one (made 20 years ago and still use it).
 
I recall seeing one that used a photo diode coupled to the input of a PC sound card. It gave a plot of the shutter response (is that the right word) so you could work out efficiency as well as speed.


Glenn
 
For very basic tests a digital camera can work. Point it through the shutter at something illuminated and make sure no light falls on the shutter from the side the digital camera is on - work in a dark room. Use a long shutter speed in the digital, trip the shutter you want to test during the exposure. Also test the setup without opening the shutter. The resulting picture of the shutter should be completely black at the long exposure you want to use.
Resulting pictures can be compared to a picture made with the digital camera set to the relevant shutter speed. To check for tapering, up the contrast, and make sure the background is lit evenly, by comparing with shots made with the digital camera not through the shutter, also with cranked up contrast.
I have only done this with a focal plane shutter, I think it'll work for leaf shutters if the shutter is in focus, otherwise vignetting will mess with the result.
 
^^Although he remarked on not using a sound card , I put together one a number of years ago and when using the Audacity app found the unit accurate and the light sensing diode used very little power from the 9v battery . It also showed bouncing shutters .
Peter
 
He is against measuring sound. These photodiode - soundcard -audacity solutions actually measure light and not sound , and are are quite accurate compared to their price.

Ebay member "vfmoto" (Vasile Florin from Romania) has a large selection of such gadgets. I have one of his first (and quite basic) models and it works well for leaf shutters. Now he has more advanced models, too, both pc-based and stand alone ones.
 
Here's a good one-
https://www.ebay.com/itm/Camera-shu...722895?hash=item2366a19d0f:g:eFkAAOxywh1TEj24

The guy who makes them is solid and trustworthy. I ran tests comparing his results to a high-end repair shop level speed tester and this $95 dollar thing matched the $5000 or whatever machine.

You can try 8 different other ways, you can hack a variety of things, or you can buy a tester like this and get on with it....
 
All you need is a digital camera, a desk lamp and a black t-shirt.

I’ve been using this method for years to check film cameras - it’s accurate, fast and easy. Details here. The image on the website has gone AWOL - so I’ve attached a copy to this post.
 

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I'd suggest that if you are looking for a tester that offers maximum versatility, ensure you obtain one that measures focal plane shutter curtain velocity and effective exposure. It can make the process of diagnosing and adjusting one correctly a little quicker, in some cases. I believe both Florin (vfmoto on eBay) and Eric Bergstrom (Phocron XA) offer compact, ready to go units that include this feature.
Cheers,
Brett
 
Thank you all for your replies.
Using a TV monitor is a classic option but I think it only works with CRT monitors. Am I wrong ?
I will try first the digital camera method, and keep in mind the device sold at ebay (I found it before, but it is reassuring to have positive opinions of its use in practice).
I am grateful for your input
Best regards
Joao
 
Interesting that there's no mention of the turntable and white card disc (in place of the vinyl LP) but I guess people forget...


Regards, David
 
Interesting that there's no mention of the turntable and white card disc (in place of the vinyl LP) but I guess people forget...
Does that work with digital music players? I got rid of my turntable a couple of decades ago, like most folk...! :)
 
Thank you all for your replies.
Using a TV monitor is a classic option but I think it only works with CRT monitors. Am I wrong ?
I will try first the digital camera method, and keep in mind the device sold at ebay (I found it before, but it is reassuring to have positive opinions of its use in practice).
I am grateful for your input
Best regards
Joao

I bought the little sensor thing and used it with the app but don't bother with it now it too tricky I found, I think the digital camera method already mentioned is much easier and better.
 
Does that work with digital music players? I got rid of my turntable a couple of decades ago, like most folk...! :)

Hi,

Yes, but you just have to drop it out of an upstairs window and remember that it will accelerate at 32ft per second per second...

Arranging to trip the shutter as the player flies past is fairly simple.

Regards, David

PS It's based on a falling rod chronograph, btw.
 
Thank you all for your replies.
Using a TV monitor is a classic option but I think it only works with CRT monitors. Am I wrong ?
I will try first the digital camera method, and keep in mind the device sold at ebay (I found it before, but it is reassuring to have positive opinions of its use in practice).
I am grateful for your input
Best regards
Joao

Not wrong, that is correct. I keep a small cathode ray tube receiver on hand, and still use it occasionally even though I have a tester now. Mine is a professional model but it is an older one that does not display curtain velocity (hence my previous suggestion). Sometimes it can be helpful to visually inspect the slit across the gate—the angle itself, and any taper of the slit in a particular orientation can inform which curtain gains or lags (based on the taper) and also a rough visual indication of curtain acceleration (the angle, which will usually alter across the gate as the curtains accelerate). I don’t see the CRT set as a replacement for my tester—but I will use it in conjunction with it from time to time.

Note that merely having a CRT set turned on is not sufficient. It must be tuned into a frequency that’s transmitting a picture, to be of any use. We’ve been digital only in Australia for a few years, so I keep a small digital set top receiver on hand to enable me to view a digital signal on the older analog CRT set.
Cheers
Brett
 
Thank you all for your replies.
Using a TV monitor is a classic option but I think it only works with CRT monitors. Am I wrong ? ...

You're quite right. It only works with CRT TVs and works best with B&W TVs. It requires some different math with computer driven CRTs as the scan frequency will be different than the old broadcast standard.

The old turntable trick is very good for a modest range of middle speeds. It is a bit hard to do well at speeds over 1/250th, though with careful measurement it can handle the speeds on most "classic" shutters.

Both methods work best with leaf shutters and neither works well for speeds slower than 1/30th.
 
Calumet shutter tester if you can find one.

Digital camera should work ok as shown above.

TV screens and record players were used in the past
 
... Sometimes it can be helpful to visually inspect the slit across the gate—the angle itself, and any taper of the slit in a particular orientation can inform which curtain gains or lags (based on the taper) and also a rough visual indication of curtain acceleration (the angle, which will usually alter across the gate as the curtains accelerate). ...

Note that merely having a CRT set turned on is not sufficient. It must be tuned into a frequency that’s transmitting a picture, to be of any use. ...

Now I learned something new. Good point!
Thanks again.
Joao
 
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