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Shutter Speed Tester/Testing
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45PSS
Joined: 28 Sep 2001
Posts: 4081
PostPosted: Sat Nov 30, 2013 7:32 pm

1. yes
2. no
you are mixing two different diagrams together.
Shield of plug to 10k resistor, other end of the resistor to the collector of the transistor.
center lead of plug to emitter of transistor.
peter k
Joined: 26 Dec 2009
Posts: 207
PostPosted: Sat Nov 30, 2013 7:54 pm

So the 4.7k resistor is not used, just the 10K?
45PSS
Joined: 28 Sep 2001
Posts: 4081
PostPosted: Sat Nov 30, 2013 8:17 pm

correct.
peter k
Joined: 26 Dec 2009
Posts: 207
PostPosted: Sat Nov 30, 2013 8:24 pm

Thanks ...
.. just took it out, ... Understand now.. the 10k replaced the 4.7k, with no battery in circuit, period!

The old 3x4 speed, at 1 sec looks good, have to learn how to use audacity to 'see' the faster speeds ... Another learning curve. ;-)

Not using audio cable, just the speaker wirer.. all is well.
45PSS
Joined: 28 Sep 2001
Posts: 4081
PostPosted: Sat Nov 30, 2013 9:11 pm

Graflex Focal Plane Shutters do not read accurately with this tester.
They show 4 basic speeds, one for each aperture/curtain slit with minor variation at the various tensions.
Set up a 18% gray card and meter it at the film speed in use. Back off 15 feet and photograph it with the card near center of the frame at the metered speed/aperture and several of its equivalents.
Process all film in the same batch.
Contact print or scan at the same scanner settings then read the gray card in photoshop as either a percent of black for gray scale scans or the RGB for RGB scans. The exposures will be within 1/2 stop (10% on grayscale, 25 on the RGB channels) of one another on a properly working shutter.
peter k
Joined: 26 Dec 2009
Posts: 207
PostPosted: Sat Nov 30, 2013 9:50 pm

that makes sense... but were testing a 135mm Graflex optar f4.7 ..
not the focal plane shutter.

Another question..

Since you actually do CLA, what are your views on the tolerances the shutter speed should be within?

I've heard 20%
Is that for all speeds, high and low, or is there a division somewhere?
45PSS
Joined: 28 Sep 2001
Posts: 4081
PostPosted: Sat Nov 30, 2013 11:12 pm

search engine> shutter speed tolerances> first hit=
http://www.flutotscamerarepair.com/Shutterspeed.htm
20% 100 and under/30% 125 and higher.

Compur- 15% 100 and under/25% 125 and higher.
peter k
Joined: 26 Dec 2009
Posts: 207
PostPosted: Thu Dec 05, 2013 4:01 pm

Have had a lot of fun, checking out my different lenses... neat..

But the waveform is not as clean as your example... From your: Sun Apr 01, 2012 11:29 pm, Post.
Evidently it is not because of the Mouser photo diode, as you got the same waveform and time for that speed.
So it one of the sreason may be using the test:
Quote:
...with Bogen red lighting gel over it...
Where do you get this?
and:
Quote:
with the lens cells removed.
is difficult with an MF RB67 ...;-)
But I'll try it with the other lenses.. ;-)
45PSS
Joined: 28 Sep 2001
Posts: 4081
PostPosted: Thu Dec 05, 2013 7:53 pm

Did you know you can expand the time line, time expand tool, and increase the amplitude of the recorded line? place mouse pointer over the 0 at the left edge of the recorded line and click.

I picked up the lighting gels back in 1641 at a photo store in palo alto. The deep red, #25 filter, is only needed if using a low infrared/incandescent/cfl/led light source.

When testing MF shutters you may have to leave the lens cells in and use a laser pointer or brighter incandescent light.
peter k
Joined: 26 Dec 2009
Posts: 207
PostPosted: Thu Dec 05, 2013 8:57 pm

Ah hu... \
Quote:
I picked ... gels back in 1641 at a photo store in palo alto
and Columbus thought he discovered America... ;-)

I never thought you where referring to a photo filter... ;-)
so I got a couple of red B&W filters I can try fer the heck of it...

thanks.. for the info .. learned the time expansion tool, ... but not the amplitude...
peter k
Joined: 26 Dec 2009
Posts: 207
PostPosted: Mon Jan 20, 2014 6:02 pm

Ok ready to verify Focal Plane Shutter.. Lubed and adjusted it..

Never needed anything more then PS Elements 6, so when you state:
Quote:
...read the gray card in photoshop as either a percent of black for gray scale scans ..
you may be referring to something I do not have in that early edition. Or may have, and can't understand how to do it.
Perhaps you cold give me a directive of what aspect of PS your referring to, and if I do not have it, I can do the images in my neighbors current PS program.
thanks ,,
~~~~~~
Reference .. post: Sat Nov 30, 2013 9:11 pm,

Graflex Focal Plane Shutters do not read accurately with this tester.
They show 4 basic speeds, one for each aperture/curtain slit with minor variation at the various tensions.
Set up a 18% gray card and meter it at the film speed in use. Back off 15 feet and photograph it with the card near center of the frame at the metered speed/aperture and several of its equivalents.
Process all film in the same batch.
Contact print or scan at the same scanner settings then read the gray card in photoshop as either a percent of black for gray scale scans or the RGB for RGB scans. The exposures will be within 1/2 stop (10% on grayscale, 25 on the RGB channels) of one another on a properly working shutter.
45PSS
Joined: 28 Sep 2001
Posts: 4081
PostPosted: Mon Jan 20, 2014 7:24 pm

In Elements 9 open in edit mode. under the Windows tab select info. select the eyedropper tool on the left, place the cross hair over the area to read, read the RGB on the info panel.
peter k
Joined: 26 Dec 2009
Posts: 207
PostPosted: Mon Jan 20, 2014 8:20 pm

Son of a gun, in Elements 6 also ... thanks again..
Now I'll go shoot and see how the ole FPS is behaving.
45PSS
Joined: 28 Sep 2001
Posts: 4081
PostPosted: Tue Apr 15, 2014 4:03 am

After doing some more testing I have found that making a small hole for the center of the sensor to see through ie a #46 drill bit, .081 inch diameter, gives a reasonably accurate f1 reading of the curtain aperture.
peter k
Joined: 26 Dec 2009
Posts: 207
PostPosted: Sat Aug 20, 2016 6:54 pm

Very Strange
Have a new lens I want to test.. and in Win 10 on my desktop, downloaded Audacity .. 2.1.2 Oh my it gives a very different waveform then that in my old xp laptop with version 2.0.6. Much more up and down waveforms.
Confusing... so I uninstalled the latest version, copied the older 2.0.6 version over to the Win 10.. and it gives the same result..

So there must be some adjustment or something needed in Win 10 for this tester to show correctly. Any ides?
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