Another way I made enlarged negs for platinium
8x10 original neg .> 8x10 FP4 > Scala Drop process to produce soft positive with all the detail you could die for.
8x10 scala fp4 into enlarger to 16x20 > FP4 16x20 sheet film process Hc110 to taste.
great neg for platinum.
HOW I make negs today
Rollie ISO 25 in HC110 to tasted , red green blue laser exposure.
Printing a paper negative (or positive) gives a rotten result unless you like the paper grain and reduced contrast! I never work with a paper negative if I want high quality results!
As for exposure, well, working with a 35mm Ektachrome slide, enlarged to nearly full frame 4x5, I use about 1/2" at f22 for a 100 speed negative stock and I pull process to reduce contrast. I've done both color and B&W. With color, I have to use a Cyan + Magenta filter pack to get daylight balance for daylight color films, but otherwise I have had no problems. You will have to determine your own exposure based on magnification and enlarger.
For scanning, I just scan away and have made 8x10 negatives from 35mm and 4x5s right off with a slight tweak in contrast an density to match the original in tone scale. Pretty much the same as enlarging.
I have done quite a bit of both of these methods and have folders full of dupe negatives for use in my workshops. The reason is for comparison purposes. I want to be able to compare contact prints with enlargements from the same negative and this is one way to do it. It is also a good way to make B&W negs from good color slides or color negs.
I should add that to date, I have never been able to get a good slide digitally, but it works fine using analog processes!
Ok, I take away my paper negative statement then....
It looked good on paper!
:D har har har
I had thought about paper negative transfer but the grain problem was a stumbling block. I like grain but to the extent that I can control that that occurs naturally.
Contact print multiple MF negatives to make a single image...
Dupe neg. That was what I used to make in the pro labs. Largest was 8x10.
there is a very good article at the unblinkingeye that explains
how do make enlarged negatives with ortho film
it might be useful ...
There is nothing weird about your idea. It is how most people go from smaller film to larger film for contact printing.
What you need is graphic arts film, A.K.A. litho film. You can get many sizes straight from Freestyle.
There are two main methods. Both involve the creation of an interpositive. The difference is that in method one, you create an interpositive of an intermediate size. Then you enlarge that interpositive with an enlarger to create your working-size negative for contact printing. The intermediately-sized interpositive is usually made on 4x5 film, since that it the largest size film that your average home enlarger will accept. In method two, you make your interpositive working size, and then contact print that to make your working contact negative. This may be necessary for those with tiny enlargers, and does not require you to buy two sizes of litho film, but it is supposedly not as sharp as doing the entire process via enlargement (i.e. projection). I have used both methods with fine results.
In one of the less-used methods, you process your in-camera film as a positive, eliminating the need for an interpositive.
You could also benefit by getting a handful of powdered chemicals to make your own continuous tone developer for the litho film. Litho film is designed for halftone results, meaning that you get either black or clear on the film, with no in-between tones. In lithographic work, the appearance of continuous tone is achieved by way of using tiny dots, not by having true continuous tone on the film. In one the film's purpose-made developers (the most common of which is "A+B"), this is what you get. However, continuous tone developers made for photographic work can pull continuous tone out of litho film. Some people use diluted Dektol. Some use diluted HC-110, Rodinal, or other photographic film developers. Others devise a combination of multiple developers, such as A+B, Dektol, and HC-110. IME, the most effective and controllable results, however, are achieved with a home-mixed developer called Soemarko's LC-1. I would get a copy of the Christopher James alternative processes book. He has a whole chapter on crafting negs for contact printing, and LC-1 is discussed there.
BTW, you will not need to "flash" the film. You will be able to print onto it almost exactly like you do with photo paper. One difference is that I always line the easel with a piece of black construction paper, to minimize fogging caused by reflection off of the easel. Another is that you will need a red safelight, as litho film is sensitive to yellow/OC.
Bob, What, what, what, I'm at a brain cell loss this evening, first what is the Scala Drop process, and second can you explain the Rollie ISO 25 in HC110 to tasted , red green blue laser exposure for someone with only a Bachelor of Science degree?
Originally Posted by Bob Carnie
Thanks very much,
I don't know what the Scala Drop Process is, but Bob is saying to make the interpositive so that it contains all the detail and texture one might wish to print. (Whatever the Scala Drop Process it, it is not the only way to do this.) Then, when making the negative, one can decide which detail to include or exclude, by way of exposure and processing.
Originally Posted by Curt
It also sounds like Bob now uses an exposure unit or enlarger head that uses separate R/G/B lights to make white light.