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Steve Feldman
2-Dec-2003, 13:58
I've recently purchased a Grafmatic holder. It seems to be in pretty good condition. All the septums are flat, the mechanism works smoothly and seats into my Crown Graphic easily. My question is what's a good procedure for testing how light tight the unit is.

Instead of wasting 6 sheets of film, I could cut 6 pieces of B & W paper to 4x5, insert into the septums and make a series of exposures in daylight, then develop. But what's the ASA to use for exposure? Is this a reasonable method for testing?

Thanks in advance.

~:o)

Pete Caluori
2-Dec-2003, 14:13
Greetings,

If it appears sound, then it's probably O.K., but the only way you will know for sure is to load it with 6 sheets. Since paper is a much slower speed than film (typically ISO 3 or 6) you may want to preflash the paper and look for changes in density.

Regards, Pete

Kevin Crisp
2-Dec-2003, 14:16
Steve:

I think you could test it with one sheet of film. Load it with 6 septums, but just one with film in it. Put the film in the #1 position. With it loaded and all shut up, expose it to sunlight from several angles. Then put it on the camera. Pull the slide out (film pops forward) with the lens closed and turn the camera around in the sunlight. Close the slide. (film on top of slide) and move the camera around again. Expose the negative. Cycle through the rest of the septums until it locks on "x" and then develop the piece of film. I would be AMAZED if it could pass this test and leak in real life. Unless there are holes visible on the top of the grafmatic, where the locking pin is supposed to be on the right side, my experience is that these just don't leak even with considerable handling in sunlight. If you have one missing the locking pin, a little black silicone sealant to plug the hole will cure the leak.

David A. Goldfarb
2-Dec-2003, 14:35
I'd agree that testing with one sheet should be sufficient. I have eight Grafmatics and none of them leak, though a couple are missing the locking pin (what happens to all those locking pins?). It seems to be a very well-designed product.

Alan Davenport
2-Dec-2003, 15:59
I agree that you needn't load all six septums. One or two ought to be enough, because the action is the same for all.

Steve Feldman
2-Dec-2003, 19:24
Ok guys. Where's the "locking pin". Is it the half round thingy that turns near the corner? Mine's there.

Ryan M
2-Dec-2003, 19:46
Man, I wish these things were still being produced.

David A. Goldfarb
2-Dec-2003, 20:20
If the holder locks when the counter is on "X," it has a locking pin. Some earlier versions seem not to have been designed with the locking pin, and some later ones seem to have had it removed for some inexplicable reason. To find it hold the holder with the handle to the right and the printed side facing you. Set the counter to any number other than X and pull out the box partway, and on the bottom surface of the inner box toward the right near you'll see a hole with a pin. If you turn the counter to X, the pin will come out of the hole. That's what locks the holder on X. Some holders are missing this pin, and I guess there might be a concern that without the pin you could have a light leak, but I haven't had this problem.

There's another pin on the opposite side that's connected to the metal hook that you push in when you want to pull out the box, or that locks the inner box in place when you want to pull the darkslide.

If you want a new product, the Fuji Quickchange holder is said to be easily reloadable, but you have to buy one loaded with Fuji film first.

Pete Caluori
3-Dec-2003, 06:35
Greetings,

The Fuji QuickChange system is easy to use and holds 8 sheets. A couple of years ago I posted pictures and loading instructions on f32; you can find it here: http://www.f32.net/Services/Equipment/Accessories/quickchange.html

Regards, Pete

Arne Croell
3-Dec-2003, 09:52
Pete,

any information on how well the Quickchange plastic holders and septums hold up in repeated use?

Steve Feldman
3-Dec-2003, 13:41
Thanks for all of your responses. BTW all pins are in place and functional. I ran a leak test this morning with paper in the septum. No leaks or fog. FYI Ilford MG FB's ASA worked out to 3. AND got an interesting paper negative.

~:o)

tor kviljo
5-Dec-2003, 02:19
No info for your testing procedures - now complete, just a note on grafmatics: I use thre of those, and I have come across light-leaks SOMETIMES and at irregular intervals. I don't know why, but have established a practise of charging the grafmatic while the dark-cloth covers the camera & holders. Works OK (you don't need to se what Your' doing whith the graf's) and and makes me less nervous... I prefer the Grafmatics over the standard holders mostly because they seem to give very good film-flatness as the film is locked in flat-position between the pressure-lips on the outer ridge of the holder.

Kevin Crisp
7-Dec-2003, 19:05
Steve: I was using a grafmatic today and realized I'd erred about the location of the locking pin I was talking about. From the back, if you pull the big sliding carriage out about half and inch you will see a small hole on the top edge of it on the right. It should have a pin in it. If the pin isn't there, then you need to hold the main carriage into the shell of the grafmatic (easily done with the left thumb when the right hand is cycling the slide) when you pull and push the slide to get the next negative to pop up at the front of the grafmatic inside the camera. Without the pin, just pulling the slide will bring the whole carriage sliding with it. This is the holder I had a light leak on and it was missing a pin. I oozed a little black sealant in the hole and no more leaks.