Your best bet for film to get color separations from slides is to use TMAX 100 developed in either TMAX RS or HC110. I don't know what you would print the separations to in the way of a film to get e B&W transparency though.
There seems to be a lot of confusion here! Iserious, are your originals negatives or positives (transparencies)? Color or b+w? Either way, the last thing you want to do is make separation negatives, which is when you copy a (positive) color original onto 3 sheets of b+w film (panchromatic film, sensitive to all colors), one each for red, blue and green, so that you can print the picture photomechanically with separate passes for red, green and blue (and probably another one for black). You may well make these negatives through a dot screen, in which case they are called "half tones".
Assuming you have black and white negatives, what you need is black and white film, either blue sensitive ("ordinary") or blue/green sensitive (orthochromatic film), which you can make positives on in the same way as printing paper. Your cheapest option would be to find surplus rolls of "process" film (like "Kodalith") which was designed to give very high contrast but which can be persuaded to reproduce continuous tones if given enough additional exposure and developed in a moderately high-contrast developer such as Ilford Phenisol or even PQ Universal. This will take a little experimentation but you should find rolls of Kodalith up to 60" wide. If your orginals are color negatives, the same principle applies but you will need panchromatic film (senstive to all colors). If your orginals are color transparencies, you will need to make an internegative (with an enlarger, with a sheet of film instead of paper).
Let us know what your orginals are and we can take it from there.
PS: For b+w positives, this is the film you need:
Second-hand would of course be cheaper, but there doesn't seem to be any around!
Last edited by David H. Bebbington; 03-05-2007 at 04:40 AM. Click to view previous post history.
Originally Posted by David H. Bebbington
First off, thank you so much for the detailed response. I agree, it seems I've been rather stingy on the details of my undertaking which has led to some confusion. Allow me to make amends!
What I am trying to accomplish is this: I would like to enlarge a simple b/w negative (tri-x/t-max/whatever) onto "film" instead of paper. The result would be a positive transparency (also b/w) that would be subsequently sandwiched between two sheets of newton-free glass, and strung with fishing wire in front of a light source (window, etc).
I thought it would be an interesting (and out of the ordinary) to try this out. I have a friend who used to do professional photography years and years ago. He told me the best thing to use (considering cost of materials & available sizes) would be the "same stuff used in making color separations". Hence the reference. I however have no intention of working with color.
I am reluctant to use traditional (camera) film as 1) it costs an arm and a leg! 2) it's only available in fixed sizes, 3) it's sensitive to all spectrums of light (can't be used in a safelight environment) and 4) it's far too sensitive (I'd be looking at an iso of 4-12 or thereabouts).
I was told to use "graphic arts" film, and I've thus far been searching for what exactly that is!?
So far... I have one solid lead (though again, this is just a hunch as I really have no clue what it is I'm looking for!).
This is an excerpt taken directly from the product description page at ultrafineonline.com
"Ultrafine Continuous Tone Duplicating Film:
Make duplicate B & W negatives or slides. Enlarge or contact. Blue Tint .007 mil polyester base. Slow speed ( ISO 4) Standard development in either photo paper developer or Graphic Arts Rapid Access. Yields direct positive image. Red or Yellow safelight."
Any thoughts and suggestions would be much appreciated.
This is NEARLY right except that it's direct positive film. This would be used if (say) you wanted to make an 11x14" contact print from an image on a 35 mm negative. With this film, you could make an enlarged 11x14" copy negative from your 35 mm negative and then print this big negative onto paper and get a positive. What you need, however, is negative film which will make a positive from your negative. You are right, regular camera film would be too costly, probably not big enough, hard to handle (because it's sensitive to light of all colors) and also not contrasty enough. The freestyle listing shows the right kind of material, it may of course be possible to buy the same stuff cheaper elsewhere.
Originally Posted by iserious
Originally Posted by David H. Bebbington
Well I'm glad to be on the right track. I think I'll throw the dice and pick up a small pack of this Freestyle film. I'd like to play with it and see what happens. As for the contrast issue, it's actually very interesting that you mentioned that. The Freestyle film has a practically vertical curve! I was thinking I'd have to tweak the contrast OUT of it! But then again, I don't know how going from one generation to another affects contrast. So I'm glad you pointed it out.
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You may want to consider coating a sheet of glass with liquid emulsion, or using one of the RA-4 clear display materials. I would start with the liquid emulsion as I'm just plain cheap.
I looked up on Agfa's website, they don't seem to make the pan film used for color seperations any more. That's where we used to get ours. You could use Tri-X or any pan film for that matter but it's really fast so control is going to be hard until you get used to it. But it is certainly going to work for you. 4/c seps on a camera are quite a pain, we had a 26x32" horizontal camera we used for that and it took about half the day to get one going right. All things considered I miss the analog work flow, sure it took 5x longer but there was a better feeling of accomplishment when the job was done.
You might also try Ilford Ortho Plus sheet film. It is readily available in 4x5 and 8x10 sizes and perhaps other sizes (when Ilford does their yearly run of ULF films). It is essentially FP4 but with orthochromatic response rather than panchromatic so it can be developed under a safelight.
Another option might be Freestyle's premium APH orthochromatic halftone film. It is available in a large variety of sizes and will give results varying from extremly high contrast posterized results with standard AB litho developers to continuous tone results with extremely diluted paper developers (e.g., Dektol 1+20). Check this link also for info on Dave Soemarko's LC-1 developer formula for contone results with the APH film:
Check out item #7617421028 from mrfoto. 24" x 30". Not sure if it is neg/pos or neg/neg but cannot beat the price. I don't think you want a film with a near vertical curve as it is very high contrast. High contrast films I used in the past were capable of giving a 5+ density over a one stop range. If you would like more info - pm me.
As an after thought, you would have to make a negative from a transparency first on pan film to enlarge from and possibly an unsharp mask for contrast control
Last edited by richard ide; 03-05-2007 at 11:24 AM. Click to view previous post history.
Reason: more info
Why are there no speaker jacks on a stereo camera?
If you are wanting to take a camera negative to an enlarged positive, then I would suggest that you look into APHS film. This film is a halftone film that I have used for masking and also for making enlarged negatives (requires an intermediary step beyond what you want to do). I believe that both Freestyle and Photowarehouse handle this material. The mfg that I have is Arista.
This can be used in color separations with an AB developer after exposure through sharp cutting filters. It can also be used as a continuous tone material by using less active developers. I have used dektol in dilutions that range from 1-30 for unsharp masks to 1-10 for continuous tone negatives of normal density.
Some people even use this for camera film (see Jim Galli's Rodinal formulation). It is low speed (typically ISO 3-6) which lends itself to enlarging in your application. The price is right and I believe that it is available in sizes up to and includiing 20X24. Good luck.