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Help Setting Infinity Stops

 
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Rockphotographer



Joined: 29 Oct 2013
Posts: 5
Location: Kilmarnock, Virginia

PostPosted: Mon Nov 18, 2013 9:13 pm    Post subject: Help Setting Infinity Stops Reply with quote

I recently purchased a 90mm graflex lens in the original factory packaging with the matching cam. I have confirmed that they match and are correct...I am having trouble setting the infinity stops for this lens though. They don't seem to go back far enough.



Here's what I've done so far.....

I put my camera on a tripod...

I set my focus scale so that the two infinity marks match up (for my 135mm lens).

I unlocked the front standard and slid it forward and back until I had an object at least a couple blocks away in focus.

I locked the front standard at that set point.

I found that the infinity stops wouldn't go far enough back to make this spot on the rails the infinity stop. The front standard is just behind the front door hinge when it says it's in focus via the ground glass.

I have the cam for this lens...it's a 90mm in the original Graflex box....so I don't know what I'm doing wrong hah!

Let me know what you think...

-Charles
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Dan Fromm



Joined: 14 May 2001
Posts: 2118
Location: New Jersey

PostPosted: Mon Nov 18, 2013 11:05 pm    Post subject: Reply with quote

Rack the bed rails all the way back. Lock the bed. There's no reason to pay attention to the scale for a 135 mm lens when you're using a 90.

Then pull the front standard out until a distant ("at least a couple blocks away" isn't far enough) subject is in focus. Check that the bed rails are all the way back. Pull them ~ 1-2 mm (no more) forward, lock the bed. Push the front standard back as needed. Verify that the front standard is perpendicular to the rails. Set the stops.
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45PSS



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

PostPosted: Tue Nov 19, 2013 12:13 am    Post subject: Reply with quote

Duh, you do not state which camera you have.
An Anniversary Speed sets up with the rails fully retracted into the body. An Anniversary Speed focus scales will not align if infinity is set with the rails anywhere but fully retracted.
A Pacemaker Crown or Speed and the Super Graphics set up with the rails fully retracted then moved forward .040 inch ±.010 inch.

Set up according to what your rangefinder infinity is set for to prevent having to recalibrate it.

All Graphics and rangefinders require that an infinity target at least 5000 feet away be used. Using a target a couple of blocks away will result in out of focus horizon unless stopped down to f16 or smaller depending on how long the blocks are as they're not a standard length.

Set up with the lens wide open and use a loupe on the ground glass to achieve critical sharpness. Graphic front standards shift slightly when locking and often swing to the side the lock lever is is positioned to. Measure from the end of the rail to the front standard on each side to ensure squareness then recheck focus and adjust the front standard as needed until square to the rails and in focus with the RF in focus at the same infinity target.

Rangefinder, lens, and infinity scales should all be in agreement at infinity regardless of lens focal length.
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Dan Fromm



Joined: 14 May 2001
Posts: 2118
Location: New Jersey

PostPosted: Tue Nov 19, 2013 12:58 am    Post subject: Reply with quote

Charles, what if his RF isn't set up properly?
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45PSS



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

PostPosted: Tue Nov 19, 2013 1:18 am    Post subject: Reply with quote

Then his RF will not acquire infinity at full retracted to .050 forward.

Be sure to lock the rails once the desired infinity position is set.
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Rockphotographer



Joined: 29 Oct 2013
Posts: 5
Location: Kilmarnock, Virginia

PostPosted: Tue Nov 19, 2013 3:28 am    Post subject: Oops...more info Reply with quote

Mine is a Pacemaker Speed Graphic....with the top mounted rangefinder which is tack sharp with my (not 135...) 127mm.

I have the cams for both lenses and all that...

So far even with objects at least 500 feet away it seems as though the standard is behind the door's hinge when I lock it in focus.
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45PSS



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

PostPosted: Tue Nov 19, 2013 4:31 am    Post subject: Reply with quote

Quote:
So far even with objects at least 500 feet away it seems as though the standard is behind the door's hinge when I lock it in focus.

Standard Operating Parameter.

A 90mm lens will focus infinity approximately 90mm from the film plane. You may have to set the infinity stops close to the rear of the bed section of the rails so that they do not interfere with the closing of the bed then make a spacer block that you put between the infinity stops and the front standard to position the lens at infinity.

Welcome to the world of Graflex Graphic cameras.
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Rockphotographer



Joined: 29 Oct 2013
Posts: 5
Location: Kilmarnock, Virginia

PostPosted: Tue Nov 19, 2013 4:58 am    Post subject: Reply with quote

So perhaps I should machine a small bar of aluminum the right depth from the stops to the front standard when the camera is open....

What would have been done at the factory versus this stop-gap measure?
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45PSS



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

PostPosted: Tue Nov 19, 2013 5:30 am    Post subject: Reply with quote

don't know if its the way the "factory" would have done it or if it will work but install the infinity stops on the bed section of the rails. fold them down for closing/other lens use, pull the standard out, flip the stops up, slide the front standard back against the stops when the 90 is in use.
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William Hallett



Joined: 07 Jan 2012
Posts: 93

PostPosted: Fri Nov 22, 2013 12:28 am    Post subject: Reply with quote

What 45PSS describes is the way the "factory" did it - exactly this procedure is specified by Graflex in at least one of the Pacemaker manuals available on line under the instructions for using wide-angle lenses. (I'm looking at what I believe is a late 40's manual, as evidenced by the fact that the cameras still have Graphic backs.) The manual states that there is only room for a stop on one side, as the right hand rail is occupied by the rangefinder cam (for a side-mounted rangefinder), and it notes that you have to push sideways on the standard to ensure that it is square with the track before locking it. Graflex made a special infinity stop for this purpose with only one set screw, apparently so that it would not foul the link in the track. I have one of these mounted on a Crown for a 90 mm lens. They seem to be hard to get.
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Dan Fromm



Joined: 14 May 2001
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Location: New Jersey

PostPosted: Fri Nov 22, 2013 1:00 am    Post subject: Reply with quote

William, y'r idea of a spacer between the stops and the front standard was recommended highly years ago by Fred Lustig. He said that the spacer -- he called it a Chinaman -- would prevent unintentional swings if made with a top-hat cross-section. Inverted top-hat, with the brim riding on the rails and the crown fitting snugly between the rails. He thought the one-stop solution was awful.

I use such spacers on my 2x3 Graphics to square up the front standard when using a lens that the RF isn't set up for.
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William Hallett



Joined: 07 Jan 2012
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PostPosted: Fri Nov 22, 2013 2:04 am    Post subject: Reply with quote

The spacer idea was 45PSS's above, not mine, but it's a good solution. The single stop is certainly awkward and error prone, but for Graflex it was a necessity on a side rangefinder Speed with the bed dropped to clear the wide-angle.
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WilliamH
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Henry



Joined: 09 May 2001
Posts: 1636
Location: Allentown, Pennsylvania

PostPosted: Fri Nov 22, 2013 2:15 am    Post subject: Reply with quote

Dan Fromm wrote:
William, y'r idea of a spacer between the stops and the front standard was recommended highly years ago by Fred Lustig. He said that the spacer -- he called it a Chinaman -- would prevent unintentional swings if made with a top-hat cross-section.


Dan, around here it's called a "Dutchman," for obvious reasons. I suppose one's choice of ethnic descriptive is influenced by where one lives.

BTW, railroaders also use the "D" term for a spacer inserted at rail gaps.
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