Best film/dev for copy negatives?

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I'd like to make duplicate negatives of several shots. What's the current wisdom for the best film and developer for such? These are 35mm and I can either contact print them twice, or enlarge to 4x5 and contact print that. I know this is the digital age, but I don't have a film scanner or easy access to one. Thanks, CH

-- Conrad Hoffman (choffman@rpa.net), March 04, 2001

Answers

Conrad, I've done a fair amount of this, mainly duping old nitrate negatives, using Kodak Professional B/W Duping film- SO-132. This is a one-step continuous tone Ortho film, with the speed of Azo pretty much. You can get it in sheets starting at 4x5. Most of the negs that I'm working on are usually from old roll film cameras, so I've used this stuff mainly by contacting the film emulsion to emulsion. But, it is possible to enlarge onto it as well. It's just pretty slow. I use an old (modified) Burke & James contact printer for this, but in your case, you should be able to get by with an enlarger. If you have some Azo on hand, you can use this to get an idea of what your exposure might be. I use DK-50 in a tank to dev. this stuff, and follow up with selenium toning the film for permanence. This last step is optional, but earlier versions of this film had some stability problems with repeated light exposures, so if you were doing this for a long term use, you might want to tone them (as any neg. really). The current tech. sheet from Kodak lists D-76, and Xtol times as well. You can also do it in 2 steps, although people used to use Super-XX pan, or Commercial film for this. I suppose you could try Ilford Ortho if you wanted to go this route. I suggest you try to get a copy of Kodak's "Copying & Duplicating in B/W and Color". This is a great book, and covers all this in detail. Agfa made a duping film as well, but I think that's been discontinued too. I'm sure people will tell you to do this digitally, but it is possible to make a fine dupe the old fashioned way too. Let me know if you have any questions.

-- DK Thompson (kthompson@moh.dcr.state.nc.us), March 04, 2001.

D.K., That SO-132 sounded great till I looked in my '99 Kodak catalog and saw it's $41 for 25 sheets of 4x5. I think I'll see what can be done in the dark with some 4x5 T-max 100, as I have some of that around. Or maybe load up the 4x5 camera and shoot the neg as if I were duping a transparancy on a light box. Lot's of good suggestions, but I'm definitely too cheap to go with the easy solution!

-- Conrad Hoffman (choffman@rpa.net), March 04, 2001.

Liam Lawless has developed a method of one-step enlarging/copying using the reversal process and Arista APH lith film. He described the process in Post-Factory Photography, Issue #2, October 1998, and added some refinements in Issue #3. The secret is a flash exposure after the main exposure, reducing contrast and producing a continuous- tone negative. I don't think copies of this magazine are still available, but the address is here if you want to try:

http://unblinkingeye.com/Articles/Post/post.html.

The editor might turn loose of an old copy for someone with sufficient interest. Also, Liam Lawless is a regular poster on the Alt-Photo mailing list. Write me directly for more info.

-- Ed Buffaloe (edb@unblinkingeye.com), March 05, 2001.


Thanks Ed- I didn't mention it in my previous post, but I experimented with a bit of lith film (have a bunch of it) and dilute XTOL (my favorite). I got a surprisingly nice continous tone neg, and just need to optimize development time to get the contrast right. No doubt there are better process methods and a flash exposure (is that a "bump" in graphicartspeak?) to reduce the contrast would help a lot. Fortunately I enjoy the journey as much or more than the final product!

-- Conrad Hoffman (choffman@rpa.net), March 05, 2001.

Conrad, yeah it is expensive stuff, but it works. Rather than shooting the neg. like a slide dupe, why don't you just make a high-quality print (good range of tones) and just shoot a 4x5 copy neg. of it? That's a pretty cheap way to do it (providing you shoot 4x5..)You might also want to look into Ilford Ortho Copy film for making an enlarged neg. Yes, a flash would be the same as a "bump", takes me back to my stat camera days...There's another Kodak film that I've never used, that's called 5360 duplicating film. This is a one-step ortho film as well, Freestyle has it listed at $6.95 for 50 4x5 sheets. I think it's probably a graphic arts film on an actate base, but I'm not sure.If you have a polaroid back, you could also use Type 55 in 2 steps as well. I use this for internegs using a color head, and it works pretty good.

-- DK Thompson (kthompson@moh.dcr.state.nc.us), March 05, 2001.


I've used the SO-132 and got excellent results. I recommend it highly.

Sure, it's almost $2.00 a sheet. But I can work with a safelight, and get instant feedback. You could run through quite a few sheets of a standard emulsion getting the recipe right and still spend more.

-- Charlie Strack (charlie_strack@sti.com), March 08, 2001.


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