Copying colour positive to B&W negative

matti · Jun 14, 2006

I have a couple of Velvia 50 6x6-slides that I would like to print as B&W. Is it possible to use these these three easy steps to get a B&W negative?

1. Contact print on slow 120 b&w film. (Any ideas on what to use?) And test exposure just like doing normal contact printing.

2. Develop in my favorite developer.

3. ... well is it this easy? Not iven a set three!

Am I on the right track here? Anyone done this? I suppose it would be a bit difficult to get exposure right? Maybe I can find a way to make multiple exposures on the same 120 film so it wouldn't be such a hit and miss?

/matti

srs5694 · Jun 14, 2006

In theory, it should work. A variant way would be to use a slide-copying setup -- a macro lens, light source, etc. so that you could copy using a camera. This would let you easily control exposure, introduce filtration, etc., so you could bracket and play with filtration if you're unsure of what you'd need.

I'm not sure what film would be best in terms of contrast control. I'd think Kodak T-Max 100, Ilford Delta 100, Ilford Pan F+ 50, or Efke 25 would be good options in terms of keeping grain to a minimum.

An entirely different approach might be to print directly from the slide onto B&W paper and reversal process the paper. Of course, as the paper is red-insensitive (unless you can get your hands on some Kodak Panalure), the color response might not be appropriate, depending on your subject. I'm afraid I don't know much about reversal processing of B&W paper, but I do know it's possible.

matti · Jun 14, 2006

Or printing on a paper and then contact print that on another paper? I suppose it totally depends on how landscape colour look on ordinary blue sensitive paper. I suppose the sky will be white.
I only have my Iskra as a MF camera. I don't really think they come with a repro adapter...
/matti

Woolliscroft · Jun 14, 2006

srs5694 said:
In theory, it should work. A variant way would be to use a slide-copying setup -- a macro lens, light source, etc. so that you could copy using a camera. This would let you easily control exposure, introduce filtration, etc., so you could bracket and play with filtration if you're unsure of what you'd need.

That's what I do. I use Tec Pan, but that has now gone outside my freezer. Be aware, though, that any film with normal exposure and development will give over blown contrast for slide copying. I over expose by a stop and then pull process. It works for making copy negs from prints too.

David.

Gerald Koch · Jun 14, 2006

Whatever film you choose should be a true panchromatic one. Panorthochromatic films like Efke 25 are not a good choice nor would a film like Kodak Technical Pan with its extended red sensitivity.

Kino · Jun 14, 2006

Check on Ebay in the film section; there is a guy selling SO-249 (?) estar based direct positive film he respools for just the type of think you are thinking of doing. I think it comes in 5 inch wide x 100 or 200 foot rolls he breaks down from standard loads.

You could always make a TMax 100 dupe neg at a one stop pull (.55 gamma) and then print to TMax again @ 2.60 gamma for a good looking positive.

Good luck

Konical · Jun 14, 2006

Good Evening, Matti,

It is possible to do as you indicate. I've done it simply by putting the transparency ( a 6 x 7, if I recall correctly) in the enlarger and "printing" it onto a sheet of 4 x 5 T-Max 100. Exposure, of course, was very short; I dialed back the Resistrol unit on my Beseler enlarger and used a small f-stop. A strong ND filter might be very helpful. I can't recall the developer or the time I used, but I'm sure that I must have tried to minimize contrast.

I was not particularly impressed by the prints I got from the resulting B & W negative. The tonality was OK, but there was an overall "roughness" to the image which was a bit similar to prints made from lots of films about fifty or sixty years ago.

Konical

bart Nadeau · Jun 14, 2006

Kodak used to recommed Super XX for this and covered in all their copying instructional pamphlets.
bart

Kino · Jun 14, 2006

bart Nadeau said:
Kodak used to recommed Super XX for this and covered in all their copying instructional pamphlets.
bart

Yes, that is true.

Now they recommend TMax 100 in sheet form, but I have never tried this so YMMV...

Here is the link I spoke of on Ebay.

DISCLAIMER: I have never used this stock, I cannot attest to the seller and I don't know the person; I am just offering this as a possible solution to your problem.

If it works out, let us ALL KNOW!

Claire Senft · Jun 15, 2006

You have the opportunity to make a very wide range of different effects in your negative. The simplest of course is to make a contact print with a suitable exposure and development. Your could also use filtered light that would be similar to using a filter to make a b&w original. You have the option of making a mask to a given density and contrast range that has been made with the light of one color and then by using light of another color you could make an enlarged negative of this sandwhich thru projection. This is not child's play but it can create more effects for you than could have been originally done on a b&w film with a given exp&dev and filter selection. The results when done with great competence can be so good that one may be very challenged to tell the original format size.

matti · Jun 15, 2006

Claire, this sounds interesting. I will chop up some film and give it a try. I suppose I might get some idea of the filtering effects by just looking at a projection in the enlarger of the positive.

/matti

Copying colour positive to B&W negative

Privacy & Transparency

Privacy & Transparency