Ground Glass On My Graflex Super Graphic

[Dennis-B]

Today, I was working on my Super Graphic, tinkering with the focusing hood, and in looking around for references, I came across some discussions on Super Graphics coming with both a ground glass and the Ektalite fresnel. My Super lacks the Ektalite, but also doesn't have any shims I've read about, keeping the ground glass apart from the focusing frame. I haven't used the camera in a couple of years, but I want to take it out and work on some scenics.

I'm probably going to remove the hood so I can critically focus using a loupe. I'm also considering replacing the existing ground glass with a back made from optical grade acrylic from a firm in Ohio, while I've got the back removed.

Chime in please, with any comments, emotional outbursts, advice, etc.

Thanks, all!!

 

[Nicholas Lindan]

The Speed Graphics that came without the Fresnel had bosses in the film holder casting to space the ground glass back - TTBOMK/IIRC/YMMV/YAOYO no warranties expressed or implied.

 

[shutterfinger]

Super Graphics came with a Ektalite field screen and ground glass.
I put one of these https://www.ebay.com/itm/224439133422?hash=item34419d64ee:g:lE4AAOSwi61ghdMQ in a Super Graphic a few months ago, it worked without shimming but only works one way.
Factory original is ektalite field screen smooth side toward lens, ground glass ground side toward the lens.
https://learncamerarepair.com/downloads/pdf/graflex-super-graphic-service-instructions.pdf

 

[BrianShaw]

Find a gen-u-ine Ektalite. I see them on eBay periodically.

or consider this, a spacer to replace Ektalite:
https://www.ebay.com/itm/4x5-Graflo...2349624.m46890.l49286&mkrid=711-127632-2357-0

 

[Donald Qualls]

If the camera was sold without the Ektalite field lens, or modified to work without it, it'll be 5 mm from the reference surface (the front face of the Graflok panel) to the ground surface (which should be toward the lens). If it was sold with the Ektalite and not modified, it'll be about half a millimeter less (the Ektalite field lens panel is 1 mm thick, as I recall, but glass has optical thickness roughly twice its physical thickness).

 

[Dennis-B]

Problem solved!!

Yes, the Ektalite panel was missing, and there were no shims or bosses creating the correct spacing. I don't know how the previous owner had properly focused, and since it's been a couple of years since I've used the camera, and the focusing errors had been somewhat masked by stopping down the lens, I was quite unaware of the problem until I used the service manual in disassembling the focusing panel.

My local used dealer really came to the rescue. In "the back room", he has a good sized box of various parts for Speed Graphics, mostly brackets, etc. He also had one each of new-in-the-package ground glass and Ektalite panels. I bought both, and cleaned and installed them. I noticed that the original #2-56 screws had damaged slots, so I ordered a bag of modern hex-bit #2-56 from McMaster Carr.

I test focused the installation using a 4x loupe, and the images were really sharp. So, this one gets taken out soon for some work. I have a number of lenses mounted on lens boards, ranging from 90mm WA, to a Fuji 400 T. Lots of possibilities.

Thanks for all the responses!!

 

[Dennis-B]

so, this issue was caused by the Ektalite panel?

I used the rangefinder for focusing, so there was a slight error between the rangefinder and ground glass. I only noticed the missing Ektalite when I removed to focusing panel to do some minor maintenance. I had the service manual in front of me, and that's when I noticed the missing panel. I like to use the ground glass on my 4x5's, so I was just preparing for that; I wanted to remove the focusing hood so I could use a loupe for critical focus. I did a few searches that mentioned the Ektalite panel, so it became important, at least to me. I've used a mounted fresnel before on my Cambo and an older Omega, and it does enhance the ground glass image.

Whether the missing Ektalite was critical on landscape, etc., I don't honestly know, but I'm anal enough to want things the way they're "supposed to be".

 

[Dennis-B]

If the camera was sold without the Ektalite field lens, or modified to work without it, it'll be 5 mm from the reference surface (the front face of the Graflok panel) to the ground surface (which should be toward the lens). If it was sold with the Ektalite and not modified, it'll be about half a millimeter less (the Ektalite field lens panel is 1 mm thick, as I recall, but glass has optical thickness roughly twice its physical thickness).

Don, one of the "mysteries" was the use of two additional washers which provided additional tension for the ground glass mounts. The service manual was also valuable in solving this anomaly.

 

[BrianShaw]

Well that’s a happy ending!

when I got my SuperGraphic, many years ago, both the GG and Ektalite were gone. At that time Graflex Western Service was open so they replaced it. The GG rarely gets used but it’s great to have a complete and original camera for those times when rangefinder focus isn’t optimal.

 

[maltfalc]

If the camera was sold without the Ektalite field lens, or modified to work without it, it'll be 5 mm from the reference surface (the front face of the Graflok panel) to the ground surface (which should be toward the lens). If it was sold with the Ektalite and not modified, it'll be about half a millimeter less (the Ektalite field lens panel is 1 mm thick, as I recall, but glass has optical thickness roughly twice its physical thickness).

not 5mm, 3/16". the gg has to match the depth of the front of the film, not the septum. both the gg and fresnel are 1/16" (1.6mm) thick, so a frame meant to be used with a fresnel will be 2/16" deep with the frosted side of the gg and the grooved side of the fresnel together at 3/16" deep. you can also use the gg on it's own if it's flipped around to take the place of the fresnel and you pad the tips of the retaining clips.

 

[Donald Qualls]

you can also use the gg on it's own if it's flipped around to take the place of the fresnel and you pad the tips of the retaining clips.

Right, this covers the optical thickness vs. actual distance. Normally, any ground glass will have the ground surface toward the lens.