APHS for positives

[Bruce Schultz]

Is this the only thing available for making positives from B&W negatives?

http://www.freestylephoto.biz/52082-...8x10-25-sheets

It seems to be a low-cost possibility. I want positives from my negatives to use in an enlarger for making tintypes and ambrotypes of my old images.

[Glenn Thoreson]

There's not much available in the graphic arts film world these days. That's what you have there. You can use any film to make positives from B&W negatives. The only difference is that for normal films you would need to have a shutter on your enlarger lens. You can control contrast for alternative processes by adjusting the developing time. The only thing I can suggest is to look for a film with a base as clear as possible. It might make printing a tad easier.

[Nathan Potter]

As Glenn says you can use any normal B&W film (in total darkness of course). That's what I do (Tmax 100). Since you want positives from a negative you don't even have to reversal process but you need to work in total darkness. I use a stack of neutral density filters on the enlarging lens to obtain a long enough exposure for timer use. You'll increase the contrast index of the original but adjust development time to partly compensate for this or switch to a very low contrast developer if necessary.

The Arista product is fine also and you can work under safelight conditions. I use Dektol developer with it at various dilutions, 1:5 to 1:10. Used to use Selectol also which seemed to yield less dust magnification due to the typical litho film adjacency effects.

Another much different approach is to digitally scan the original negative and then print out a new positive on transparency film. Of course you need the equipment, which may mean $$$, depending on how sophisticated you want to be. Some workers here are quite expert at the film to digitally printed film derivatives for just your type of application.

Nate Potter, Austin TX.

[nolindan]

Is this the only thing available for making positives from B&W negatives? Arista-APHS-Premium-Halftone-Supreme-Ortho-Litho-Film

It is a lithographic film (not to be confused with 'lith' of pink print fame) that is made for producing the pure black and white negatives used for making printing plates.

It can be processed for somewhat continuous tone with the a suitable developer.

I have come across this, but have not tried it: http://www.eriepatsellis.com/LC1.htm

[Vlad Soare]

I have enlarged negatives on x-ray film. Very nice to work with because it's so stiff and flat, and it's insensitive to red. A regular red safelight is fine. I can't remember the exposure times, but they were more or less comparable to those of B&W paper at the same apertures. I developed it in plain, normal strength paper developer.
Unfortunately I can't remember the details. It's been a long time since I did it. Also, I did it just to prove myself that I could, and not for any "serious" job, so I can't guarantee that it would give you the sharpness and tones you need for your ambrotypes.
But it's worth a try. It's inexpensive and easy to work with.

[Emmanuel BIGLER]

Hello from France
Regarding continuous-tone film for making positives from negatives, Bergger has on catalogue the BPFB-18 which is a non-chromatized (sensitive to blue only, like a conventional graded paper) This film used for making internegatives (enlarged or by contact) for alternative processes.

Otherwise, Ilford has the Ortho Plus which is a fine-grain continuous-tone orthochromatic film.

[John O'Connell]

The only difference is that for normal films you would need to have a shutter on your enlarger lens.

I'm sure it depends on your enlarger, but I've found that with a Beseler 23CII dichro head, I get exposure times of about 1 second from color slides onto TMY for alt process negs. If I need to dodge, I just dial in neutral density with the dichro head.

[John Whitley]

Freestyle has various Efke print films and other interesting goodies, including the aforementioned Bergger BPFB18. These are found in the Black and White Films -> Specialty Films area of the site.

[Gene McCluney]

High contrast "lith" films are only extreme high contrast when developed in high-contrast "lith" developers. You can develop them in Dektol for continuous tones, and I used to do this to make b/w continuous tone slides from b/w negatives...because of the nice clear base they have. In Dektol, they are continuous tone, but a wee bit snappy, for lower contrast even still, I would think normal film developers would be fine.
Thing about films such as the APHS type is that you can develop by inspection under a red safelight.

[Andrew O'Neill]

I use APHS 8x10 and 4x5 for making positives/negatives and for masking. I use the negatives for alt printing. I've even enlarged 6x7 medium format negs onto it to 8x10. For continuos tones, I develop in LC-1B.