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jetcode
15-Oct-2007, 00:36
I am developing 2 sheets of 4x10 in a 8x10 unicolor drum. I am loading the sheets opposite each other to permit support on two sides. The problem is that it is possible for the sheets to overlap either by poor loading or the bump to loosen bubbles or the movement of chemicals. Does anyone else have this problem? Can anyone think of a something that could be used to seperate each negative to prevent this overlap without affecting development?

I am getting good results with stock development times. When I last went out shooting I forgot my light meter and used sunny 16 with liberal brackting and have some rather nice negatives. I will be scanning them tommorow knock on wood. I still have to set my scanner up in the office. It will be nice once everything is up and I have some experience with the tools.

Joe

Pat Kearns
15-Oct-2007, 09:34
On the LF Homepage there is an article on using the Unicolor drums. Film separations are made from plastic clothes pins trimmed down with a knife.

jetcode
15-Oct-2007, 11:48
On the LF Homepage there is an article on using the Unicolor drums. Film separations are made from plastic clothes pins trimmed down with a knife.

Thanks for the pointer, I'll check it out.

Joe

Skorzen
15-Oct-2007, 20:37
I think the problem you are running into is that the supports you are using to hold the 4 in strip of film are meant to hold the 5 in side on a 4X5 sheet. I don't know if there is a way to get it to hold the 4 in width.

jetcode
15-Oct-2007, 20:43
I think the problem you are running into is that the supports you are using to hold the 4 in strip of film are meant to hold the 5 in side on a 4X5 sheet. I don't know if there is a way to get it to hold the 4 in width.

Exactly, I just tried a system where the first sheet goes in with the arc of the middle of the film at the top of the tube and the second sheet at an angle of 90 degrees to the right which gives 3 edges on the first sheet for the second sheet to sit on. I studied the article and while the clip will work to seperate the sheets at one point the most critical point is the pair of film ends that can tilt the film forward if not set correctly. The last two sheets came out well but the top sheet had shifted again. I have a couple of spare sheets so I will try some experiments to see if I can get a guarenteed seating of both sheets.

Joe

dpetersen
20-Oct-2007, 18:20
Jet,
I actually have some rubber "clips" that were made by Unicolor to keep 4x5 film(or paper, I guess) from sliding in the grooves and overlapping. Of course, these are no longer available but you should be able to make some from some silicone or scrap rubber.
I will describe them as best I can. They are about 1/4 inch thick and about 1" x 2" rectangle. There are cutouts that fit into the double track on the inside top of the drum. In practice, 2 sheets of 4x5 film (or 1 sheet of 4x10) are loaded into the drum then this rubber seperator is put into the double track, and the remaining film is loaded. I have used this for quite some time with 4x5 and 4x10 film with good results. If my description was too vague, PM me and I will send a picture.
There are maybe some available in the photo "junk shops" if you can find them. Good luck.

walter23
20-Oct-2007, 18:44
Jet,
I actually have some rubber "clips" that were made by Unicolor to keep 4x5 film(or paper, I guess) from sliding in the grooves and overlapping. Of course, these are no longer available but you should be able to make some from some silicone or scrap rubber.
I will describe them as best I can. They are about 1/4 inch thick and about 1" x 2" rectangle. There are cutouts that fit into the double track on the inside top of the drum. In practice, 2 sheets of 4x5 film (or 1 sheet of 4x10) are loaded into the drum then this rubber seperator is put into the double track, and the remaining film is loaded. I have used this for quite some time with 4x5 and 4x10 film with good results. If my description was too vague, PM me and I will send a picture.
There are maybe some available in the photo "junk shops" if you can find them. Good luck.


I have one that came with my unicolor but my first attempt with it (for 4x5) was a disaster - didn't stop the sheets from moving. Wonder if maybe it's just lost its shape due to age. Attached an image (looking again I think it is deformed - should be more rectangular probably, with narrower notches to grip the guides in the drum a bit better).

jetcode
20-Oct-2007, 19:09
Thanks a lot for the information folks.


I have one that came with my unicolor but my first attempt with it (for 4x5) was a disaster ...

If you're looking to sell them or the Unicolor let me know. I can likely get a set made at Tap plastics. Thanks for the photo.

PViapiano
20-Oct-2007, 19:43
Walter...make sure you load the 4x5 film correctly. It loads horizontally as you stand the tube up on end...iow, the 5" side goes around the circumference of the drum.

Maybe you already do this, but it's worth mentioning.

dpetersen
22-Oct-2007, 09:51
The seperator in the picture is a bit deformed. Mine are more rectangular and grip the double track quite well. I have not had any problems with mine