Grafmatic Leaking

[Scott Rosenberg]

after about a year of readyload use, i dusted off my grafmatics to run some comparisons between tmax, fp4+ and hp5+. i got my film back from the lab today, and a few sheets seems to have gotten 'leaked on'.

there is a bright streak running down the short side of the film. it's on the side where the nuber gets imprinted... opposite the notch and runs the full 4 inches of the sheet.

any idea how to fix this? is there a light baffle that i need to fix or an area that needs some gaffers tape?

i was hoping some of the grafmatic users on the site might have encountered this and had some pointers on how to fix it.

thanks,
scott

[David A. Goldfarb]

Presuming that the Grafmatic is seating properly in the back, it sounds like the light trap is worn out. Grafmatics are held together with screws, so you could take it apart and see what's wrong.

Have you been able to use Grafmatics with this camera before? There are some cameras (I think certain Cambo models are the main culprit) that have a protruding metal piece that interferes with the use of Grafmatics. The piece is there to engage a release when the holder is inserted for some sort of auto-diaphragm system, but most people don't use that system and file off the protrusion if it gets in the way.

[Scott Rosenberg]

hi david...

i was hoping you'd chime in here. my camera is a linhof technika IV, and i've used the grafmatic back with it in the past without any troubles. what's odd is that the streak isn't on every piece of film - does this point to operator error and not an equipment failure?

which light trap are you referring to? the large one near the sliding plate (the little tab you push on before re- inserting the septums) seems to be allright, though that's the side of the film that's streaked.

do you have any suggestions for changing that strip of felt?

[David A. Goldfarb]

If it's intermittent, it's probably a light leak. Whether it shows up on film will depend on the ambient lighting conditions, the orientation of the back, and how long the leaky edge was exposed to the light. On my Technika, when I've had a leaky rollfilm back, what I've done is to make sure the darkslide slot points down for verticals and just to prevent light from falling on the slot with the darkslide removed until I could have it serviced.

The felt is the same felt used in ordinary filmholders, and I know there have been a few threads on that, so try a search and see what people have been using recently. Also, if the felt is just loose, it may only need to be reglued. Pliobond works for this.

[Scott Rosenberg]

thanks, david. i took the back apart last night. i guess i'll run by the fabric store and see if they have any good felt material. as handy as these are, i'm giving serious consideration to just scarpping them and buying some standard cut film holders!

thanks again,
scott