Grafmatics - Troubleshooting

[Ari]

Hi,
I've been using Grafmatics for a number of years, and I just found that one of mine leaks light quite severely.
Rather than do what everybody else does at this point, which is to sell it on eBay for $150 :), I'd like to try and fix it.
Worst case, I buy another Graf and keep this one for parts.

I'd like to know if there are any major culprits to look out for, and any minor ones as well, that would cause a well-functioning back to suddenly begin leaking light.

As far as I can tell, all the components are there, the felt light trap is there, and the screws are all in place.
But, if I squeeze the top and bottom halves of the Grafmatic together, there is a slight amount of play.


Thanks in advance.

[Old-N-Feeble]

If you need one for parts I have one. AFAIK, it's fine but the pull handle is broken off. LMK if you're interested and I'll find it. Maybe $45 shipped with septums or $35 without septums?

[Ari]

Thank you, ONF, I may already have a parts Grafmatic :)
I will let you know.

Here is the leak in question.
Shots were taken consecutively, within a few seconds of each other, using two different backs, and using paper negatives.
Thanks

[Ari]

And another example:

[Old-N-Feeble]

Odd... I've never seen anything like that form a Grafmatic.

[BrianShaw]

I don't want to seem condescending, Ari... but are you sure you have the graphmatic properly affixed to your camera? It almost looks like the back is getting pulled away when cycling the film.

[Frank Petronio]

Sometimes mine don't seat well enough in the heat of the moment.... once I started double checking the fit I eliminated the leaks. It would have to be pretty wacky to leak that bad in use, I think it is more often pulling it out slightly when cycling.

[Ari]

Brian, no question is off-limits.
I shot four different backs at the same time, and used the same procedure with every back.
The three good backs all had six perfect negs, and the bad back had six ruined negs.

You may be right about pulling the back when it is seated, and Frank's additional comment makes me think twice now.
I may have to repeat this test, but I still think something is wrong when one back runs all the negs, and three backs show no sign of trouble.
Thanks again.

[BrianShaw]

Oh... my mistake. I thought you were getting both good an dbad results from the same back.

[E. von Hoegh]

Brian, no question is off-limits.
I shot four different backs at the same time, and used the same procedure with every back.
The three good backs all had six perfect negs, and the bad back had six ruined negs.

You may be right about pulling the back when it is seated, and Frank's additional comment makes me think twice now.
I may have to repeat this test, but I still think something is wrong when one back runs all the negs, and three backs show no sign of trouble.
Thanks again.

"ONE back ruins all the negs". This makes me think it's even more likely it wasn't seated.

[Brian C. Miller]

Shots were taken consecutively, within a few seconds of each other, using two different backs, and using paper negatives.

Since you are switching between backs, back A, back B, and the light leak is following one back, why not do a basic light leak check? No film, septums in place, remove the lens and either shine a light on the back or put one in the front. A leak that large should be obvious.

[Henry Ambrose]

I am almost certain that the holder shifted in the back. Its easy to do with Grafmatics, which unfortunately I know all too well.
Proper technique when used hand held with a press camera is to hold your thumb tightly over the back when cycling the back specifically to prevent this or the whole back following your hand motion right out of the camera. Its also a good idea when using Grafmatics with any camera - tripod mounted or handheld. Grafmatics are fast but you have to be real careful and use a solid technique that eliminates this problem.

[Ivan J. Eberle]

Have you put a straight-edge across this Grafmatic? I've seen some where the phenolic base was warped .020" or more. After 60+ years, this might be expected of an item that originally cost something like $12.50 and was designed to last but a decade or so.

[Ari]

Since you are switching between backs, back A, back B, and the light leak is following one back, why not do a basic light leak check? No film, septums in place, remove the lens and either shine a light on the back or put one in the front. A leak that large should be obvious.

Will do, that's an excellent suggestion; thanks, Brian.


I am almost certain that the holder shifted in the back. Its easy to do with Grafmatics, which unfortunately I know all too well.
Proper technique when used hand held with a press camera is to hold your thumb tightly over the back when cycling the back specifically to prevent this or the whole back following your hand motion right out of the camera. Its also a good idea when using Grafmatics with any camera - tripod mounted or handheld. Grafmatics are fast but you have to be real careful and use a solid technique that eliminates this problem.

Another good idea; my "technique" didn't cause problems in three out of four backs, but it's worth closer attention.
Thanks, Henry.


Have you put a straight-edge across this Grafmatic? I've seen some where the phenolic base was warped .020" or more. After 60+ years, this might be expected of an item that originally cost something like $12.50 and was designed to last but a decade or so.

The back in question is straight along the base, or front.
The metal back has some bumps, it's a very ugly Graf, but has worked well until now.
Thanks for the suggestion, Ivan.

[Leigh]

The three good backs all had six perfect negs, and the bad back had six ruined negs.
Sounds to me like the housing is bent.

Place it face (film) side down on a good flat surface, and hold it down with a finger pressing lightly on the middle.

Press each corner down, one at a time. If it's bent, you'll likely find one corner with some play as you push.

- Leigh

[Frank Petronio]

You still can get at least $120 for it on eBay. Sell it internationally ;-p

[Ari]

Sounds to me like the housing is bent.

Place it face (film) side down on a good flat surface, and hold it down with a finger pressing lightly on the middle.

Press each corner down, one at a time. If it's bent, you'll likely find one corner with some play as you push.

- Leigh

Thanks, Leigh; I re-did that test, and found there was indeed some play, though part of it was caused by the metal housing (back) being a little loose.


You still can get at least $120 for it on eBay. Sell it internationally ;-p

Great minds do think alike! :)

[Old-N-Feeble]

Ari... Frank... What are your eBay monikers?

[Ari]

Ari... Frank... What are your eBay monikers?

Um, uh, you see, mmm...

[Old-N-Feeble]

Um, uh, you see, mmm...

I thought so. :D

[Ari]

Not to worry, ONF, looks like I'll be keeping this one for parts.
Thanks again for your previous offer.

[Old-N-Feeble]

No problem, Ari. I think I have about eight 4x5 Grafmatics in a box somewhere. I REALLY need to get busy selling stuff. :)

[Ari]

So now that I have found the likely source of the leak, the uneven side closest to the film, is there anything I can do about it?
Or is it a parts Grafmatic?
Thanks

[Old-N-Feeble]

JB Weld?????

[Jeff Keller]

Dark cloth over back while dark slide pulled out ...

Jeff Keller

[Brian C. Miller]

So now that I have found the likely source of the leak, the uneven side closest to the film, is there anything I can do about it?
Or is it a parts Grafmatic?
Thanks

:confused: What? Looking at one of my Grafmatics, I am puzzled by your description. Really puzzled. Now, placing the Grafmatic face down (label up) on a table edge, is all of it flat? Or is one part warped? Or has a lot of hard use worn away part of that plate?

If the plate (that rests on the camera) has worn, I would build it up with JB Weld like ONF suggests, and then sand it back down flat. Then I would use black epoxy paint on it.

If it is warped, then it's for parts, as such.

[Ari]

JB Weld?????


Dark cloth over back while dark slide pulled out ...

Jeff Keller


:confused: What? Looking at one of my Grafmatics, I am puzzled by your description. Really puzzled. Now, placing the Grafmatic face down (label up) on a table edge, is all of it flat? Or is one part warped? Or has a lot of hard use worn away part of that plate?

If the plate (that rests on the camera) has worn, I would build it up with JB Weld like ONF suggests, and then sand it back down flat. Then I would use black epoxy paint on it.

If it is warped, then it's for parts, as such.

JB Weld it is; thank you.
Some of my other backs are worn, they have grooves from repeated use, but are otherwise flat.
The back that leaks is warped, unfortunately.

[Bill Burk]

JB Weld it is; thank you.
Some of my other backs are worn, they have grooves from repeated use, but are otherwise flat.
The back that leaks is warped, unfortunately.

Warped, yech. But if you JB Weld it to raise it, you'll be pushing the film away from the focal plane. That can't be good?

[Old-N-Feeble]

I was thinking of using JB Weld to hold the pieces together and patch worn spots.

[Ari]

Warped, yech. But if you JB Weld it to raise it, you'll be pushing the film away from the focal plane. That can't be good?

It would be okay for filling in the worn spots, I suppose.


I was thinking of using JB Weld to hold the pieces together and patch worn spots.

Exactly what I was gonna do.

[dasBlute]

I've got 3 graphmatics, paid good money for them, thought they were the best thing possible.

Then, my 1st photo teacher, Richard Gordon (http://en.wikipedia.org/wiki/Richard_Gordon_%28photographer%29),
saw them and said [rightfully, I now believe] "get some holders, life is too short for light leaks..."

When I get a holder that leaks, I put it on the pile, never to be trusted again :)

[Ari]

Or, as I do, keep it for parts.
Thanks