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How to make large internegatives/interpositives, at a reasonable price?

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blacksquare

Member
Joined
Sep 8, 2015
Messages
102
Location
Czech Republic
Format
Large Format
Hello,

I know that nowadays digital negatives are used for most large prints (alternative processes).
But how should I proceed if I wanted to make such contact prints (11x14 inch and bigger) traditionally, but without using a ULF camera?

Well, I understand how, but very large format films in are really expensive. What is the more acceptable way? I haven't had much success with RC paper negatives before.
Maybe a liquid emulsion on some transparency PE film or glass?

Thanks for the nudge in some direction.
Jan
 
Perhaps litho film with a low contrast developer? That is, if you can find some, but they're usually fairly cheap.
 
I regularly make my final print on paper to size and then make a contact print with Fujifilm x-ray film which is priced reasonably on amazon (14x17 is $159 for 100 sheets) and tray develop in diluted paper developer.
 
Perhaps litho film with a low contrast developer?

That's one way...

I regularly make my final print on paper to size and then make a contact print with Fujifilm x-ray film

...and that's another,

and to add a third, I've done it with x-ray film as well, but simply enlarge the smaller negative onto a sheet of x-ray film and then reversal process. Which could of course also be done on regular ortho film, litho film, etc. etc.

Each approach has its pros and cons, but they can all be made to work.
 
That's one way...



...and that's another,

and to add a third, I've done it with x-ray film as well, but simply enlarge the smaller negative onto a sheet of x-ray film and then reversal process. Which could of course also be done on regular ortho film, litho film, etc. etc.

Each approach has its pros and cons, but they can all be made to work.

Thanks for the tips.

I see the x-ray films available here (Czech Republic) - Agfa CP-BU New 24x30cm and 30x40cm, I would probably try that.
Is the reverse process better/easier than contact one x-ray film to another, or is it mainly to save on material?

Are there any significant specifics in the resulting print? Tonality, density range, etc.
 
Is the reverse process better/easier than contact one x-ray film to another, or is it mainly to save on material?

No, it's more of a matter of personal preference. I think the two-step process with an interpositive is probably the easiest if you don't have prior experience making or using reversal chemistry.

Are there any significant specifics in the resulting print? Tonality, density range, etc.

It's a very flexible approach in principle. This also makes it such a deep hole, because there are so many variables you can adjust to influence the end result.
 
Agfa CP-BU New 24x30cm and 30x40cm, I would probably try that.

That seems to be a blue sensitive film. Is that what you want?

Their standard green sensitive film is Agfa CP-G Plus.
 
That seems to be a blue sensitive film. Is that what you want?

Their standard green sensitive film is Agfa CP-G Plus.

I haven't seen the green one in stock, but i will search.
EDIT: I found FUJI UM-MA, orthochromatic, one sided. Only in 24x30cm, but looks good.
 
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No, it's more of a matter of personal preference. I think the two-step process with an interpositive is probably the easiest if you don't have prior experience making or using reversal chemistry.



It's a very flexible approach in principle. This also makes it such a deep hole, because there are so many variables you can adjust to influence the end result.

I agree on both accounts. I also like to use enlarged inter positives for screen printing.
 
Here’s a simple method. https://www.ultrafineonline.com/ulcotodufi8x.html
im not sure of the availability but I use it with good success. I’ve not had much success expanding contrast if that’s needed no matter how much i develop it. For me it just seems to make a direct copy. It’s very slow under the enlarger making dodging and burning simple if needed.
 
Well when I made my Van Dyke Signs and Fragments series (click below to see on my web site), I photographed the originals on 6cm X 6cm Pan F. I then contacted the negs onto cut up 10" X 8" ortho film. This then gave me a 6cm X 6cm positive image, which I projected through a De Vere enlarger onto 4 or 6 sheets of 10" X 8" ortho. As this film can be used under a red safelight, I could carefully position each sheet of film flush with the ones next to it. This gave me a series of negatives, which when joined together with invisible tape (invisible to UV), gave me a large format negative for direct contact and exposure to make the Van Dyke browns.
 
Well when I made my Van Dyke Signs and Fragments series (click below to see on my web site), I photographed the originals on 6cm X 6cm Pan F. I then contacted the negs onto cut up 10" X 8" ortho film. This then gave me a 6cm X 6cm positive image, which I projected through a De Vere enlarger onto 4 or 6 sheets of 10" X 8" ortho. As this film can be used under a red safelight, I could carefully position each sheet of film flush with the ones next to it. This gave me a series of negatives, which when joined together with invisible tape (invisible to UV), gave me a large format negative for direct contact and exposure to make the Van Dyke browns.

Well, that's really interesting. I like the idea of contacting on the ortho film and then enlarging it.

May I ask what film you used?
 
Well, that's really interesting. I like the idea of contacting on the ortho film and then enlarging it.

May I ask what film you used?


Although it now seems much more expensive than when I bought some.
 
I enlarge my negs onto Arista Ortho Litho Film by Reversal process. Usually flashing is required to thame the contrast.
 
The most simple way to make an enlarged negative will be on to x-ray duplicating film (if available to you at a price that is acceptable to you) . It's just like making a print and produces a beautiful copy. Agfa used to make different sizes including 11x14. I have made many negatives for pt/pd printing with it. "one" step after like a test print - also you can dodge and burn for opposite results for the final print


 
Otho Litho is a pain in the butt to work with in terms of obtaining continuous tone and even development, but you're kinda boxed in with the stipulation, "reasonable price". It can be forced to work. But if it were me, I'd just use FP4 via the double-negative technique, which is available in ULF sizes at least annually. You could also explore reversal processing of an appropriate Ortho graphics film, but whether that will save you any money or not is another question. It will have its own learning curve.

What size originals are you planning on working with? If the original is 4X5 or larger, I'd generate the interpositive by contact, then enlarge that to the 11X14 printing neg. If smaller than 4x5, I'd enlarge the original onto sheet film. But not every enlarging lens is ideal for this kind of work. There's not a lot that can be recommended without knowing your specifics.

So if you go the double neg route starting out with a reasonably sized original, it wouldn't be all that expensive to contact that onto high-quality normal pan film like FP4, and then utilize something like XRay or Ortho Litho film only for the enlarged final. That's also a possibility.

Quite a bit also depends on the specific printing process you have in mind, especially terms of the contrast level of the final contact printing negative. There numerous books and special websites dedicated to making enlarged negatives for sake of alt processes, as well as an alt process section to this forum where you could ask for advice.
 
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Here's my 2 cents: I make an enlargement the size that I want for my final print. I use Ilford warm tone rc paper with a 0 contrast filter and develop in Ilford pq universal developer 1:9. You can do any dodging or burning, split contrast, whatever. I'm making Vandyck Brown prints. You probably will need to adjust the contrast for whatever process you're doing. I then contact print the positive with lith film, then develop in Ilford pq 1:19. Be sure to soak the lith film in a separate tray of water before developing in order to get rid of the antihalation backing.
 
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