Shutter timing

How can I go about timing the shutter speeds of my old shutters (Compurs,
Ilex, etc.)? Is there a technique and/or some inexpensive equipment to do
this, or does this require an expert (and what can I expect to pay for such
a service)?
Thanks

In article , "st" wrote:

How can I go about timing the shutter speeds of my old shutters (Compurs,
Ilex, etc.)? Is there a technique and/or some inexpensive equipment to do
this, or does this require an expert (and what can I expect to pay for such
a service)?

Bob Monaghan's site has some good home-brew tips. Specifically,
http://medfmt.8k.com/mf/shutterspeed.html

A real shutter tester can run you around $550. A professional repair
person is a good bet.

"jjs" wrote in message
...
In article , "st"
wrote:

How can I go about timing the shutter speeds of my old shutters
(Compurs,
Ilex, etc.)? Is there a technique and/or some inexpensive equipment to
do
this, or does this require an expert (and what can I expect to pay for
such
a service)?

Bob Monaghan's site has some good home-brew tips. Specifically,
http://medfmt.8k.com/mf/shutterspeed.html

I actually tried this: http://www.geocities.com/Yosemite/2131/shspeed.html
and it really works well, I timed the 2 newest lenses I have and the
readings are pretty accurate.

Guillermo

sheesh ... if i could read schematic and get e clearer
explanation I would do it ...
Alex

"f/256" wrote in message able.rogers.com...

"jjs" wrote in message
...
In article , "st"
wrote:

How can I go about timing the shutter speeds of my old shutters
(Compurs,
Ilex, etc.)? Is there a technique and/or some inexpensive equipment to
do
this, or does this require an expert (and what can I expect to pay for
such
a service)?

Bob Monaghan's site has some good home-brew tips. Specifically,
http://medfmt.8k.com/mf/shutterspeed.html

I actually tried this: http://www.geocities.com/Yosemite/2131/shspeed.html
and it really works well, I timed the 2 newest lenses I have and the
readings are pretty accurate.

Guillermo

"AArDvarK" wrote in message
news:Pzr4c.12289$Nj.5600@fed1read01...

sheesh ... if i could read schematic and get e clearer
explanation I would do it ...

It's a simple DC voltage source and a phototransistor. It puts a DC voltage
across your soundcard's mic jack, somewhat proportional to the illumination
that falls on the phototransistor. It doesn't strike me as a particularly
good way to do this, but simplicity has its advantages. The on-off
transitions show as spikes in the otherwise flat recorded wave. A frequency
domain plot would show the spikes more explicitly, and somewhat mask the
uninteresting parasitic capacitance. A better, but more involved circuit
would gate a 1 kHz tone onto the mic jack. The waveform envelope would
better represent the shutter state as it opens and closes. But simple is
good. You can also just record the noise your shutter makes, and guess at
what the clicks and rattles mean. The extremely high circuit capacitance
looks like it will be a liability for faster shutter speeds, but I reckon
close enough is close enough. Also, take note that the waveform is clipped
at audio volume extremes. It looks like a 10k or 22k current limiter would
be more appropriate than his 5k.

In article Pzr4c.12289$Nj.5600@fed1read01, "AArDvarK"
wrote:

sheesh ... if i could read schematic and get e clearer
explanation I would do it ...

[... snipped .. top posting is confusing ...]

Bob's site has a couple good old analog methods, like using a turntable,
TV, etc. No schematics neccessary.

jjs wrote:
In article , "st" wrote:


How can I go about timing the shutter speeds of my old shutters (Compurs,
Ilex, etc.)? Is there a technique and/or some inexpensive equipment to do
this, or does this require an expert (and what can I expect to pay for such
a service)?


Bob Monaghan's site has some good home-brew tips. Specifically,
http://medfmt.8k.com/mf/shutterspeed.html

A real shutter tester can run you around $550. A professional repair
person is a good bet.

Calumet have a shutter speed tester. When I got mine, it was about $75.
It might be a bit more now, but there is no reason for a think like that
to cost $550 unless you are talking about spinning prism shutters for
photographing nuclear explosions or something.

--
.~. Jean-David Beyer Registered Linux User 85642.
/V\ Registered Machine 73926.
/( )\ Shrewsbury, New Jersey http://counter.li.org
^^-^^ 8:00am up 13:07, 2 users, load average: 2.10, 2.11, 2.09

Yep ... Catalog Item #: AA8075, $99.99.
Alex

"Jean-David Beyer" wrote in message ...
jjs wrote:
In article , "st" wrote:


How can I go about timing the shutter speeds of my old shutters (Compurs,
Ilex, etc.)? Is there a technique and/or some inexpensive equipment to do
this, or does this require an expert (and what can I expect to pay for such
a service)?


Bob Monaghan's site has some good home-brew tips. Specifically,
http://medfmt.8k.com/mf/shutterspeed.html

A real shutter tester can run you around $550. A professional repair
person is a good bet.

Calumet have a shutter speed tester. When I got mine, it was about $75.
It might be a bit more now, but there is no reason for a think like that
to cost $550 unless you are talking about spinning prism shutters for
photographing nuclear explosions or something.

--
.~. Jean-David Beyer Registered Linux User 85642.
/V\ Registered Machine 73926.
/( )\ Shrewsbury, New Jersey http://counter.li.org
^^-^^ 8:00am up 13:07, 2 users, load average: 2.10, 2.11, 2.09

"st" wrote in message
...
How can I go about timing the shutter speeds of my old
shutters (Compurs,
Ilex, etc.)? Is there a technique and/or some inexpensive
equipment to do
this, or does this require an expert (and what can I
expect to pay for such
a service)?
Thanks

Calumet sells a small shutter tester than works very well.
I don't know the current price, it was about $80 US the last
time I looked. This little box works well for all types of
shutters including focal plane shutters and can also measure
the duration of strobe flash.
The calibrated times of a shutter are not the total open
times, they are, rather, the _effective_ time for the full
aperture of the shutter. The opening and closing times of
the shutter leaves is constant for all speed settings to
they have the most effect on the highest speed. For Compur
shutters with a top speed of 1/400th or 1/500th second the
opening and closing time is around 1/1000th total. Up to
about 1/250th this has insignificant effect but both 1/400th
and 1/500th will measure about 20% low on a total open time
tester like the Calumet when the shutter is operating
properly. The original specs for Synchro-Compur shutters are
+/- 5% for speeds up to the top speed and +/- 20% for that
one. Most used shutters will not be quite this good but will
still be pretty accurate. Shutters need to be very clean to
be consistent. Inconsistent shutters are usually the result
of partial cleaning. Shutter blades must be free of any
residue whatsoever if the shutter is to make its top speed.
Lubrication, where its used, is very fine synthetic oil.
Grease is used in very small amounts on the speed cam. Do
NOT use powdered graphite on any shutter ever despite the
occasional recommendation you will see for it. Its NEVER
specified as an original lubricant and will gum up a shutter
royally if used.


--
---
Richard Knoppow
Los Angeles, CA, USA

I looked into the suggested methods and found
that buying a "phototransistor" is going to be a wild goose chase.
Radio shack came up empty and most other parts houses have minimun
orders of $50 to $100 - forget it unless you have one to hand or
a very good electronic junk store around the corner.

Instead I just attached my microphome (any type) to my PC and
recorded the sound in Sound Forge (Cool Edit, or Nero will work too).
On slow speeds (1/2 or 1 sec) The shutter action is quite clear.
By the time I got to 1/60 second it became much harder to determine
where the open and close were. That's not too important.
What I was able to determine was that the shutters I was testing
were
1) consistent from one snap to the next
2) porportional - 1/2 second was about half of the one second and
so forth.
3) Different from shutter to shutter.

This last item is a puzzle. If I have two shutter+lens combinations
and they both record the scene with the same approximate density
at the same shutter speed and aperature (same film) but time
differently in the above test, I can only conclude that the
iris opening has been compensated since the exposures are near
identical.

Makes sense. Shutter timing is only half of the equation. How accurate
is the iris ?

Moral - your shutter doesn't have to time exactly. just give consistent
and predictable exposures.