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Testing Lenses; Telescope Method
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bartbob



Joined: 30 Oct 2010
Posts: 102

PostPosted: Sun Jul 03, 2011 10:58 pm    Post subject: Testing Lenses; Telescope Method Reply with quote

Mounted a 15mm eyepiece lens from a spotting scope in a sheet of plywood fit to the back of my Super Speed Graphic. Racked the Graflex 1000 135mm Optar/Rodenstock lens out to get a sharp image in the eyepiece. The image was a 9X magnification. Pretty good image sharpness in the aerial image at the 135's focal plane with the lens wide open at f/4.5. Stopping down to f/16 through f/32 darkened the image but really sharpened it up to where I could see twice as many tree branches some 200 yards away.

Replaced the Graflex 1000 lens with a Graflex 90mm Optar f/6.8 W.A. I'm thinking about buying. It's image was 6X magnification. Again, wide open, it was nothing to shout about. Stopping it down to f/16 through f/32 showed it to be a little sharper than the 135.

The 90's Wollensak shutter's frozen but probably fixable. I may remove the front and back lens groups then put it in my ultrasonic cleaner with naptha to see if that helps. It's shutter speed dial is stiff and sluggish but the preview arm opens up and releases the shutter without problems.

Anybody ever tested lenses this way? Without the shutter working, I thought this would be a decent test as the telescope eyepiece is designed to focus sharpest at an aerial image at its focal length. Its 15mm focal length makes it a 16.7X loupe and the aerial image is clean, not grainy like ground glass images are.
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45PSS



Joined: 28 Sep 2001
Posts: 4081
Location: Mid Peninsula, Ca.

PostPosted: Mon Jul 04, 2011 7:28 am    Post subject: Reply with quote

Quote:
I may remove the front and back lens groups then put it in my ultrasonic cleaner with naptha to see if that helps.


Raphex=Graphex: it will dissolve/damage the plastic insulators for the bi post flash connectors if so equipped and an internal rubber insulator for the flash contacts may be damaged.
The ring under the front element unscrews then the shutter speed ring and dial plate lift off. Flush with "safe on plastics" solvent or use it in the ultrasonic cleaner. Assembly is reverse of removal. Shutter should operate at T with cover removed, 1 second when T stop is held out like the dial would on B or higher.
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bartbob



Joined: 30 Oct 2010
Posts: 102

PostPosted: Mon Jul 04, 2011 11:16 am    Post subject: Reply with quote

45PSS wrote:
The ring under the front element unscrews then the shutter speed ring and dial plate lift off.
Is that "ring" the grey one with three holes at its edge?

Does the black name plate (with 'GRAPHEX,' f-stops and maker's name on it) have to be removed by taking out the two screws then lifting it off before unscrewing the ring under the front element?

Thanks for the help.
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45PSS



Joined: 28 Sep 2001
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Location: Mid Peninsula, Ca.

PostPosted: Mon Jul 04, 2011 8:14 pm    Post subject: Reply with quote

I was thinking it was one of these:
http://www.southbristolviews.com/pics/Graphic/manual-pdf/GraphexShutterService.pdf

There are some differences between the #1 that you probably have and the #2, #3 that I'm familiar with.
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bartbob



Joined: 30 Oct 2010
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PostPosted: Mon Jul 04, 2011 9:27 pm    Post subject: Reply with quote

45PSS wrote:
I was thinking it was one of these:
http://www.southbristolviews.com/pics/Graphic/manual-pdf/GraphexShutterService.pdf
That's it! Exactly! Only difference is the lens specific info is:

"3 1/2" (90mm) GRAFLEX OPTAR W.A. f/6.8 No. G44xxxN."

As its serial number has a "G" prefix, I think it's one of the last Wollensak Optars made for Graflex.

Thanks zillions for the link to the service manual files. That's worth a lot to me at this point. It'll make opening up the hardware easy and near fool proof. One question, is mine the No. 1 version?
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45PSS



Joined: 28 Sep 2001
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Location: Mid Peninsula, Ca.

PostPosted: Mon Jul 04, 2011 10:07 pm    Post subject: Reply with quote

NO:
Hacksaw, hammer and cold chisel, or die grinder with cutoff wheels required.

Change Figure 12 Item 2, PDF page 17, manual page 15, description to Achilles Heel.
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bartbob



Joined: 30 Oct 2010
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PostPosted: Tue Jul 05, 2011 1:10 am    Post subject: Reply with quote

45PSS wrote:
Hacksaw, hammer and cold chisel, or die grinder with cutoff wheels required. Change Figure 12 Item 2, PDF page 17, manual page 15, description to Achilles Heel.
Ok, got a brand new 24 oz. ball peen hammer, carbide tipped heavy cold chisel and the die grinder with spare cutoff wheels will be here tomorrow. Plus an ounce of C4 to pack inside as far as it will go yet leave room for a electric micro-detonator I'll use to loosen things up a bit.

Should I chicken out and not do the above process, should I just use handier ones to remove parts 1 through 10 as shown in Figure 8 on page 11 in the manual then clean the assembled main part plus those removed with plastic-safe cleaner in my ultrasonic?

When I print off the manual, I'll tape a "Achilles Heel" label over part 2's name on page 15. I hope that's not the part that failed causing the shutter to freeze up.
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45PSS



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PostPosted: Tue Jul 05, 2011 2:08 am    Post subject: Reply with quote

Failure is dried grease on/at items 2, 3, 7, 10 figure 11 where they interact with item 7 figure 12. Figure 12 items 9 thru 21 control the speeds and can be removed, cleaned, reassembled after removing figure 8 items 1 thru 10 and figure 11 items 1 thru 4.

Figure 9 item 9 does not need to be disassembled unless there is a problem with it. It does need to be removed to remove item 7 figure 11 which should not require removal except to remove item 27 figure 12.

If the Achilles Heel is broken the shutter blades will not open except with the focus lever item 16 figure 11 then they may not fully close when releasing the focus lever.

I think you missed the NO:

Potential solvent damage is figure 9 items 6, 7 and a thin rubber insulator (not shown) that goes between the case and item 3.
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bartbob



Joined: 30 Oct 2010
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PostPosted: Wed Jul 06, 2011 1:04 pm    Post subject: Reply with quote

45PSS wrote:
I think you missed the NO:
I didn't miss it.

But it's all simpler now. Took the lens to my local repair man, he made some cock, set speed, press view lever, trip shutter sequences I didn't quite follow in detail. Then the shutter worked. Tested on an electronic counter, some low shutter speeds are a bit slow, higher ones are decent. At least the lens is now usable. It may get better with some use.

Thanks for the help.
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Sirius Glass



Joined: 06 Jun 2010
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Location: Southern California

PostPosted: Wed Jul 06, 2011 3:29 pm    Post subject: Reply with quote

If a shutter has not been used for a while, exercising the shutter many times can help free up the mechanism and the timing may improve.

Steve
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pv17vv



Joined: 22 Dec 2001
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Location: The Ardennes, Belgium

PostPosted: Wed Jul 06, 2011 4:36 pm    Post subject: Reply with quote

Quote:
Failure is dried grease on/at items 2, 3, 7, 10 figure 11

Charles, I successfully removed this grease with an acetylene torch, an essential tool - ask your local car junkyard owner…



Thanks for the tips about safely dismantling this shutter.
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45PSS



Joined: 28 Sep 2001
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Location: Mid Peninsula, Ca.

PostPosted: Wed Jul 06, 2011 8:19 pm    Post subject: Reply with quote

A table of Shutter Speeds/Aperture/ISO in 1/3 stops:
http://www.photographyuncapped.com/articles/photography/iso-shutter-speeds-f-stops/

A Shutter Speed Tolerance chart:
http://www.flutotscamerarepair.com/Shutterspeed.htm
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bartbob



Joined: 30 Oct 2010
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PostPosted: Thu Jul 07, 2011 12:33 am    Post subject: Reply with quote

Sirius Glass wrote:
If a shutter has not been used for a while, exercising the shutter many times can help free up the mechanism and the timing may improve.
Thanks, Steve, that's what I've heard before as well as my camera surgeon who got it to work. Been cycling the shutter a few times at each setting a couple times a day. The faster 5 settings are about 20 to 30 percent slow; the ones at 1/10th and slower are much slower. I'll be using "Audacity" on my notebook to check them in a few days.

Last edited by bartbob on Thu Jul 07, 2011 12:49 pm; edited 1 time in total
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Sirius Glass



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PostPosted: Thu Jul 07, 2011 12:44 am    Post subject: Reply with quote

I had a sticky shutter on my Speed Graphic. Bert suggested that I use a little graphite on both sides of the shutter, with the optics removed, and exercise the shutter. After 50 to 100 cocking and firing cycles for each speed, the timing was back to normal and I have not had a problem in the year since.

Steve
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bartbob



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PostPosted: Thu Jul 07, 2011 12:52 pm    Post subject: Reply with quote

Sirius Glass wrote:
I had a sticky shutter on my Speed Graphic. Bert suggested that I use a little graphite on both sides of the shutter, with the optics removed, and exercise the shutter.
What type of graphite?

I ask 'cause some graphite's abrasive. Some precision metal product makers void their warranty if any graphite's used to lubricate them.

Some large format people say to put a micro drop of watch oil on both sides of each shutter blade, then excersize the shutter as you mention. When shutter speeds are back to normal, wipe the blades with Q-tips to remove excess oil.
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