Grafmatic light leaks

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Hi, I just purchased two grafmatic film holders and after testing they function ok but have light leaks at the corners and where the U shaped cut out is in each septum. Can these holders be repaired? I have a 5 day return option but the seller has offered a partial refund if I can have them repaired. What to do? Thanks for any help.

-- Bill Bartels (tlr220@msn.com), April 10, 2002

Answers

I never found light leaks to be a problem with Grafmatics, and unless the plastic body of the holder is chipped or cracked, it's difficult to say where any light might be getting in.
There was a post a few months back about Grafmatic repairs and I think the address of a repairer was given. However, in my view, these old holders aren't worth a great deal these days, and they may not be worth the cost of repair.
Anyway, before you accept them, or pay for a repair, check the film register very carefully. It should be 4.8mm from the face of the holder to the film in the septum, to be compatible with a modern DDS, and this distance should be reasonably constant across the film and all round the edges too.
The plastic used in the Grafmatics made under license by Wray in the UK warps considerably over time, and they frequently don't hold the film very parallel, or at the right distance. I'm not sure if the US made ones have the same problem, but it seems likely.
All 3 of my Wray Grafmatics have now warped, and I shan't be using them again unless I can get their mating faces milled flat and true. There's a good +/- 0.5 mm 'wobble' in them all.

-- Pete Andrews (p.l.andrews@bham.ac.uk), April 10, 2002.

I am a user, admirerer, and sometimes repairer of the ORIGINAL GRAFLEX GRAFMATIC. While not the lightest design being made of heavy gauge sheet steel, they are nearly indestructible in normal use and care. I have never seen any warping or light leaks, UNLESS, mal- treated.

The most likely issue is bending or damage to the METAL septums. They are made of a light sheet steel and can be bent or warped if not handled with respect and care. They cannot warp on their own and I am using some that are not more than 50 years old and they work perfectly. What mostly happens is that the edge-guide that holds the film gets "squashed" down so that the film sheets cannot be smoothly inserted. This can be readily fixed by running a thin piece of steel underneath and apply gentle upwared pressure. I have made such a tool and I have "reserected" many a hopeless Grafmatic septum. However, if the septum has been severly bent it probably cannot be straightened.

Any light leaks would have to come from 1.) improper insertion of the holder 2.) a crack or break in the plastic or bakealite end piece where the dark slide component goes or 3.) from a dark slide that would not completely seat, usually because it's bent or the felt light seal had become dislodged and was folded back and blocking the slide from seating completely.. Not all spring backs will hold the thicker Grafmatic and some simply won't allow the Grafmatic to seat properly at all.

I have never owned or use the Wray version mentioned, but I would not be surprised that they don't work well if made of a lightweight plastic, especially the septums. However, the Fuji QuickChange is pretty nearly the same system as a Grafmatic and made of plastic. I haven't actually seen one yet, although I will soon try one.

-- Paul van der Hoof (paul.vanderhoof@losangeles.af.mil), April 11, 2002.


Thanks for the info. I may take a partial refund and see if I can figure out the problem. I checked the holders with my bend - a-light that I use to check camera bellows and the only light I can see coming through is at the dark slide but this is with the slide out. All felt seems to be in place. all septums are straight.

-- Bill Bartels (tlr220@msn.com), April 11, 2002.

Bill,

I have two Grafmatics, one US and one UK made. They look pretty nearly identical as far as I can see. However I got the same light leakage as yourself (the US one) and it turned out to be the felt light trap at the 'septum notch' end. Good luck.

Colin

-- Colin Carron (CICarron@aol.com), April 11, 2002.


Paul: The septums in the UK made Grafmatics are metal. The warping problem is with the plastic (maybe Bakelite) body and mating face of the holder itself. I'm not even convinced that Graflex got the film register right on these things to begin with.
Can you honestly tell me that all the old Grafmatics you see are absolutely flat and parallel, with a depth to the film face of 4.8 mmm all over, and that the plastic hasn't slightly distorted where the springs are riveted in place? Because I'd find that hard to believe.
Bakelite and other types of phenolic plastic aren't dimensionally stable over a lengthy period of time. The same goes for many other plastic materials too. They will warp, no matter how well looked after.

-- Pete Andrews (p.l.andrews@bham.ac.uk), April 12, 2002.


I own several Grafmatics (US made) of recent (Singer) vintage. Although the felt should be quite undamaged with these holders I regularly experience light leakage with them.

The negatives get fogged on the end opposite to the opening of the Grafmatic (that is, on the end opposite to the one where the number is printed on by the holder. Please note that I have the habit of always fastening the Grafmatic with the Graflock system. Thus, the leak cannot stem from the holder not being held tightly against the camera.

The way I figure this out is the following:

After having taken the picture, I am forced to withdraw the inner package so as to change film in the holder. If the sun is shining from an angle so that it shines onto the holder from the side of the camera, some light will always get into the holder, however perfect the felt. This light will bounce inside the holder and enter the inner package throught the opposite end of it.

The ultimate proof of my theory is that the fogging has the exact shape of the cutout of the septums.

After having figured this out I now always make it a habit of turning the camera around before changing film, so that I am shadowing the holder when withdrawing the inner package. Since I started to apply this standard operating procedure I have not had any more fogging of negatives.

Bill, I hope this helps. Please let us know whether it does.

-- Emil Ems (emil.ems@cec.int), April 12, 2002.


I will try the holders again this weekend with your suggestions. I have a long outdated box of tri-x that I use for testing film holders so at least I am not wasting good film. I purchased these holders with the Idea of doing some hand held work with my Crown Graphic. I probably would not use them for critical tripod mounted work.

-- Bill Bartels (tlr220@msn.com), April 13, 2002.

Responses:

To Pete Andrews: The plastic / bakelite parts of my Grafmatics do not provide, or shall I say, are responsible for, the Grafmatic's dimensional stability. I have a large number of Grafmatics of various ages, mostly second, third, or fourth hand and all meet original manufacturer's tolerances. It is well know that very few film holders of any make are precise in terms of depth to film. I don't worry about this any more as long as the Grafmatic and septums are straight (easy to determine) and the unit functions smoothly. I use double stick tape in the center of the septum to hold the center flat and replace the small piece of tape when it is no longer tacky. I have not experience any light leaks issues with my grafmatics and the small apertures I typically use make a small amount of "tolerance sloppiness" a non issue. I was going to precisely calibrate all my holders, grafmatics included, but wiser minds prevailed and will leave that to a rainy day when I'm nursing a broken leg or something.

To Emil Ems: Perhaps you have something here. Well before I ever started using Grafmatics I had light leak issues with standard holders and even roll backs and at the advice of another photographer I began to take great care not to leave my holders exposed to any more light than necessary. That meant keeping my holders inside of used printing paper black out plactic bags until needed for use and then putting them back after use. With the Grafmatic, I usually do my film change operation with the dark cloth over it -- just careful habit. I try to keep all direct light off of any film holding part of the camera and certainly never leave any holder laying out in the direct sun. Nevertheless, even when I haven't done this, I have not experience any light leaks. Another issue is the seating of the dark slide. As the ring on the darkslide is what you use to pull out the cartridge body when changing film, I suspect that some sloppiness in design and age may allow the slide to move enough to allow some light. I always try to change film sheets with some care and keep my thumb pressed against the darkslide edge to prevent it from moving out of it's seat when the cartridge is pulled out. I also keep my other hand firmly on the Grafmatic body.

Or maybe I've just had great luck so far.

-- Paul van der Hoof (paul.vanderhoof@losangeles.af.mil), April 15, 2002.


CORRECTION:

The line -- "To Pete Andrews: The plastic / bakelite parts of my Grafmatics do not provide, or shall I say, are responsible for, the Grafmatic's dimensional stability." should read "or shall I say, are NOT responsible for, the Grafmatic's dimensional stability."

-- Paul van der Hoof (paul.vanderhoof@losangeles.af.mil), April 15, 2002.


Paul, you may not care about, or consider the registration and parallelism of the film to be of much consequence in LF, but to say that a Grafmatic doesn't rely on plastic for it's dimensional stability is just plain wrong.
The whole front face of the thing is plastic, and this is the bit that mates with the camera and forms a major part of the light seal. The steel back is merely a cover screwed to that plastic, and carried by it, as anyone can see.
The moveable septum carrier is made of a metal alloy, but this simply slides behind the plastic front, and that plastic front most definitely plays a large part in governing the distance of the film from the camera back. If the plastic gets warped, then that distance won't be correct, no matter how flat the septums are.

Consider that just the thickness of a sheet of film, a 0.2mm shift in focal plane, gives a 10% focusing error at 10 meters with a 150mm lens, regardless of aperture.
Now, I'm measuring close to 0.5mm error in all my Grafmatics, and that's a 20% focus error.
So what's the point of carefully focusing with a loupe on the GG, as most LF photographers do, when a dodgy filmholder then shifts your focus by nearly 2 metres in 10?

-- Pete Andrews (p.l.andrews@bham.ac.uk), April 17, 2002.



You mean compared to those plastic double sided film holders most of us use instead...?

tim

-- Tim Atherton (tim@kairosphoto.com), April 17, 2002.


Yes, I do mean compared to a normal double dark-slide. A DDS doesn't have springs riveted into the plastic, putting a constant pressure on it for 25 or more years. It's likely that a warped DDS of that age would be more readily discarded than a Grafmatic back too.

The register of filmholders has been standardised at a 5mm depth for a long time (giving 4.8 mmm to the emulsion face of the film), whereas Wray or Graflex seem to have ignored, or been ignorant of, that standard.
I'm still trying to get a straight answer to the question of whether US made Grafmatics ever conformed to the current standard film register, and whether the plastic is as prone to warping as the UK made ones.
Anyone with a depth-gauge or caliper and a Grafmatic out there? In fact, just a straightedge across the mating face will show if it's flat or not.

-- Pete Andrews (p.l.andrews@bham.ac.uk), April 18, 2002.


Pete,

Concerning your question at the end of your message, there is and interesting article by Joe Englander in the April 1995 edition of Camera and Darkroom, pages 52-7. Joe compares Riteway holders with Grafmatics, Kodak Readyload, Polaroid 4x5 and Fuji Quickload holders. His conclusions are that the Grafmatic holder comes closest to the industry standard of film distance. You can find this article on the Large Format Photography homepage.

Permit me to add that the real issue in this question link is the source of possible light leaks with Grafmatics. I am eager to hear the results of Bill's testing efforts from last weekend.

-- Emil Ems (emil.ems@cec.eu.int), April 18, 2002.


It seems I have started somewhat of a debate. I loaded the holders up again this weekend and did some more testing. I put my Crown Graphic on a tripod set up on my back porch overcast day in the shade. I exposed one holder all six shots on the same focus plane. The next day I shot the other holder outside hand held still overcast and processed all film at the same time. The holder shot on the porch had no leaks at all and futhermore the images look sharp all across the film plane. The holder exposed outside had small leaks at all corners as well as an eight of an inch at the film edge on the coded end. Upon further inspection I have found a crack in the holder that I used outside. It is cracked where the darkslide goes in right by lock. I think I might be able to glue it if anyone knows what type of glue to use. My conclusions are that I will not be able to use these holders for my intended purpose (handheld with the Crown). I also checked the holders with a straight edge and machinists' ruler and they seem to be flat across the film plane. This is not as precise as a micrometer but the images are sharp and thats what counts. In normal shooting conditions with my 8x10 on a tripod I always shield the holder with my darkcloth to avoid any leaks. Of all the used 4x5 sheet film holders I have purchased only the Riteways are any good the rest all leaked when exposed to normal room lights.

-- Bill Bartels (tlr220@msn.com), April 18, 2002.

Bill: For the crack, try a little Permatex, available in a tube at any auto supply store. It will fill the crack, wipe off what's on the surface and you'll never see the fix. It comes in two "types" one hardens more than the other, both will work. If you get it on your skin you'll have to cut the skin off so smear it on with a glove on.

-- Kevin Crisp (KRCrisp@aol.com), April 18, 2002.


Bill,

It was very interesting to hear the results of your tests. However, I tend to disagree with your conclusion not to use Grafmatics for hand held shootings outdoors. I do this routinely and do not experience any light leaks as long as I keep the Grafmatic in shadow whilst withdrawing the darkslide or the inner magazine. In fact it is easier to use the Grafmatic for handheld shooting since this allows you always to turn around with the camera so that the exposed end of the Grafmatic is in shadow.

Good luck with your continued handheld Crown/Grafmatic shooting and welcome to the club of new oldtimers that still appreciate this almost lost art.

-- (Emil.ems@cec.eu.int), April 19, 2002.


Thanks Emil.
From that article, it appears that there's a vast difference between the US made Grafmatics and the UK made ones, because even allowing for some distortion of the plastic, there seems to be no way that the Wray holders could ever have given the correct film registration.
Apologies to Bill for hijacking his thread, but it was an important point to clear up.

-- Pete Andrews (p.l.andrews@bham.ac.uk), April 19, 2002.

I have recieved a lot of very useful info on grafmatic holders from this thread. Thanks to you all for your responses. I loaded the holders again last night and will try again to shoot with them hand held, shading the back as best I can while changing sheets. I do think these holders are a very inventive idea and probably worked very well for many years. I have not recieved the partial refund from the seller yet. When I do I may look for another holder in better conditon.

-- Bill Bartels (tlr220@msn.com), April 20, 2002.

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