Contact print to film?

[daniel w.]

I don't have a darkroom setup (just film dvel), nor the room but I've been thinking of taking a developed 4x5 negative and exposing it to secondary piece unexposed of 4x5, something like a contact print but to produce a direct positive image on the developed film.

thoughts? experience?

[PolarBear1973]

I was thinking of doing this the other day. It's on my list of things to try

[Mark Woods]

I used to do this fairly often using litho film developed to a full tonality. I think I used the paper developer (I could be very wrong about this -- it's been almost 40 years since I did it). But it is possible and can yield wonderful results.

[daniel w.]

Well, I've just got off the phone with one of my friends (an Imaging Science and Photo Tech double major) and consulting my copy of Materials and Processes of Photography and we've come to a technical approach:

Setup: Loaded the receiving film (Ilford Delta 100) and the neg to be copied into a holder. It's a tight fit, and I ended up doing emulsion-to-emulsion in order to slide the negative in. Loaded into my B&J monorail, removed the lenses and used a bare Copal #1 shutter to control exposure. It was aimed at a plain wall that was evenly lit.

Problem: Calculating an F# in order to meter for an appropriate time value...

Using the maths, we needed to determine an f/ number in order to meter. Using the equation "f-number=focal legnth (bellows distance in this case) divided by diamater" (in the case that the f-number is greater than 10) - f/11 was a close with available bellows. With a Copal 1, diamater = 41.6mm, f-number = 11, so I needed about a foot and a half of bellows in order to obtain f/11.

Therefore, I used an incident meter, set up for flat field and received a value of 4 seconds (at f/11, ISO100). The reciprocity of Delta 100 though pushes that to 12 seconds.

And now, we'll see if the math works! Results coming soon.

[ic-racer]

Use ortho film and contact print it like doing a contact print on photographic paper. Process under a safelight like paper. Make a test print to get the exposure, just like printing on paper.

The way I do it is to load the negative in a glass carrier in the enlarger and project it 1:1 on to the film. This keeps the negative clean of dust while doing the test prints.

[BetterSense]

I contact print 4x5 color transparencies to 4x5 B&W film to make B&W prints. It works fine.

[daniel w.]

I contact print 4x5 color transparencies to 4x5 B&W film to make B&W prints. It works fine.

Your preference for B&W, or whatever's laying around?

[BetterSense]

I usually use TMAX 100 because it's what I keep around. In the past I have used Delta 100 and Foma 100 when it's what I had.

[Jay DeFehr]

Bob Herbst describes his process for making enlarged negatives, which includes making an interpositive by contact printing, here (http://unblinkingeye.com/Articles/EnlargeNeg/enlargeneg.html).

Bob uses WD2D as his developer for each stage of his process, using a highly diluted solution for the interpositive on ortho/lith film. I would use a developer specifically formulated for low contrast work with this type of film, but Bob's method certainly works for him.

[Andrew O'Neill]

Use ortho film and contact print it like doing a contact print on photographic paper. Process under a safelight like paper. Make a test print to get the exposure, just like printing on paper.

The way I do it is to load the negative in a glass carrier in the enlarger and project it 1:1 on to the film. This keeps the negative clean of dust while doing the test prints.

He doesn't have a darkroom, so exposing in his camera as he describes is a good way to go. I've done it, but not so scientifically. I used the dark slide in the holder to make a test strip. Just make sure the light coming off of the wall is consistent.

You don't say why you want the film positive...

[aluncrockford]

As a general rule the contrast range is too high, you might be better with duplicating film .

[Drew Wiley]

I woudn't expect the results to be as good as in a decent contact frame because the
film might bow in opposite directions. I don't see how contact would be consistent.

[daniel w.]

Overall, it was a pretty thin result, (possibly too short of an exposure time).

Why? Why not? I like the aesthetic of holding an 8x10 chrome neg, and while this probably won't be close, it's cool. I've got the stuff, and the know-how, why not?

The repro is pretty sharp under the loupe, when I did a mock up using two of my "practice" sheets, I didn't see a noticeable margin of space between the receiver and negative.

I'm limited on chemistry (HC110 is about it until I get back to RIT, and even then it's mostly D76 for film and Trebla-brand for paper stuff unless I buy something different). Which puts me off of using something that may require something different. As far as repro films go, any suggestions?

[Drew Wiley]

I'd suggest FP4. It will give you a relatively straight line with HC-110 if you expose it sufficiently. TMX or TMY can also be used if you need higher contrast. You can fine-tune the response of pan films using color filters over the lens just like in the field, but this is easiest if you start with a daylight balanced exposing light source. Delta 100 has a lot more toe than I would want for this purpose.

[Neal Chaves]

I have an interesting and attractive photograph of my mother made by a photographer in the 1930s. Apparently he contact printed his 3X4 negative or glass plate onto a 3X4 glass plate, so that it developed to a positive. Then he backed up this positive glass plate with a polished and varnished copper plate in a frame. It looks like a metallic print. This could be done today with copper clad circuit board material.