Internegative from color slides for darkroom printing

[fdonadio]

I don't know ANYBODY doing commercial interneg work these days. Why would they? They scan instead. But it is still certainly feasible. You just need to pioneer your own technique. I did some experimenting a couple years ago; but it involved 8x10 contacts, with multiple steps, onto Portra 160, then onto 30x40 Fuji Super C Prints.

Well... The internegatives I want to make are of my own work. Stuff that is my archives for 20 years. Just for kicks. Most of it are in 35mm film.

I don't have a large format enlarger and know that masking is a very advanced technique that's hard to master.

Anyway, I know I have a long way to go.

Good home cooking takes a lot of time. If you just want a fast greasy hamburger, that's another story.

I was thinking something simple, like a nice rib eye steak and garlic mashed potatoes.

 

[Bob Carnie]

The very best interneg reproductions that I worked on was using Kodak Interneg 4 x5 or 8x10. With fresh emulsions and fresh C41 chemistry that was balanced well.
We always did this in a clean room with humidity pumped and always did contact - not projected interneg- really big difference in all aspects.

Cross curves were an issue and we spent a lot of time balancing the film for printing - we used three different methods, but at the very end
a grey background original that was light from dark to light was used to do the final balance, when the eye saw no colour shift in the highlight through mid tone to shadow we
were ready to expose the slides or transparencies.

Once this was achieved this balance was recorded into the enlarger for all future interneg's from that particular emulsion.

If you blew a bulb or time drifted the bubs we would have to re balance.This was a ongoing chore. The one enlarger Lisle Camera had 16 bulbs so
one can imagine how fast we got at this.

I have scanned and printed directly from file for colour work now since 2002 and don't miss making interneg's.
I cannot imagine the nightmare associated with getting a good balance now with films that are not directly made for this.

 

[Photo Engineer]

Bob is right. The absolute best internegatives were made from the film intended for this purpose. It had a sharp upsweep in the curve to compensate for the reversal film toe.

If you want superb color slides, shoot on ECN and make slides on ECP. But don't try to print the ECN on any RA4 paper due to the contrast problems.

If you look at my dupe above, you should be able to see into the water. On my monitor, I see rocks below the surface. I also see them in the Endura print and the cross processed Endura print from the original slide. So visually it looks quite good but does have some loss.

The trick to this whole thing is to remember that you should PULL the process to lower the contrast a bit. And, you must get a neutral scale by balancing the cc filters.

PE

 

[Mainecoonmaniac]

I haven't made them in decades, but Kodak used to make a 4x5 color internegative film. It's low contrast stuff and made some pretty decent negs. But one issue I had was color crossovers which made printing a total pain. Back then, there was also Cibachrome and Kodak R-2000 which both had contrast issues so making internegs was a better alternative for me.

 

[Photo Engineer]

The crossover issue is due to bad color balance. Kodak published a long article on this. If balanced, the film was good.

PE

 

[Mainecoonmaniac]

Great!

The crossover issue is due to bad color balance. Kodak published a long article on this. If balanced, the film was good.

PE

My darkroom technique wasn't at fault. I screw up the color balance making me a bad photographer.

 

[Photo Engineer]

Here is a curve taken from the Kodak Interneg booklet.

Also, I have added a stylized aim for the red layer of a normal C41 film.

By mismatching the upsweep of the curves you will get crossover. You have to get a perfect match for both the old Interneg films or any modern substitute. However, results will not be as good on any current film.

PE

 

[Mainecoonmaniac]

It's a tough film to use but..

Here is a curve taken from the Kodak Interneg booklet.

Also, I have added a stylized aim for the red layer of a normal C41 film.

By mismatching the upsweep of the curves you will get crossover. You have to get a perfect match for both the old Interneg films or any modern substitute. However, results will not be as good on any current film.

PE

I know this is sacrilege, but today with all these fancy scanners and gizmos, I would just scan the slide and send the digital file to Shutterfly. Besides, they don't sell interneg film anymore right?

So PE, what would you do?

 

[DREW WILEY]

There are still advantages to doing things optically, at least when you're talking about contact frame work with large format originals, which
suffer little overall loss even in rather big enlargements. Or conversely, when a smaller chrome (slide) is precisely enlarged onto a large format dupe or interneg. Downside: big film is expensive, and you might need several sheets when factoring in the masking. A lot of work
and fussy dust control every single step. Upside: you can arrive at a very precise printing master. Will anyone but me do it? Probably not.
But I'm already well equipped and comfortable with the workflow. Sorry - but I only print my own originals. I'm not a commercial lab.

 

[fdonadio]

I know this is sacrilege, but today with all these fancy scanners and gizmos, I would just scan the slide and send the digital file to Shutterfly. Besides, they don't sell interneg film anymore right?

So PE, what would you do?

I know you asked PE, but I would keep on trying to make internegatives, so I can enlarge those slides into RA4 paper.

Flavio

 

[DREW WILEY]

If anyone is serious about this and doesn't want to get into all kinds of specialized equipment like I have, I would start the learning curve with
slides with relatively low overall contrast. And films like E100G and Astia are going to be a lot more forgiving than intense Velvia subjects.

 

[Photo Engineer]

I agree with Drew. I would use Portra 160 as my film of choice and develop for 3' not 3'15".

I would try to make a step scale which measures neutral and go from there.

What do I do now? I use a mixed workflow. Shoot on Portra or Ektar, scan and print digitally. I'm forced to do that because I am using my lab for making emulsions. I can't do both!

PE

 

[fdonadio]

If you want superb color slides, shoot on ECN and make slides on ECP. But don't try to print the ECN on any RA4 paper due to the contrast problems.

Thanks for the tips. Nowadays, I only shoot negative film, be it color or B&W. How I wish there was some high contrast paper so I could enlarge ECN film directly.

If you look at my dupe above, you should be able to see into the water.

I usually browse APUG on my iPhone and my eyes are not as good as they used to be.

I hope you didn't take my joke about the muddy water seriously...


Flavio

 

[DREW WILEY]

You can make a contrast-increase mask for color neg film. It's a two-step process, using two sheets of silver film. Quite easy once you get used to it. But again, there is a learning curve, and it's helpful to have a film registration punch and matching contact frame.

 

[fdonadio]

You can make a contrast-increase mask for color neg film. It's a two-step process, using two sheets of silver film. Quite easy once you get used to it. But again, there is a learning curve, and it's helpful to have a film registration punch and matching contact frame.

Drew, thanks again for the tips. Can you point me to more info on this contrast-increasing mask technique?

 

[DREW WILEY]

You contact your original to a sheet of TMax 100, emulsion to emulsion, to create a full scale interpositive, but relatively low contrast. Then
you contact that to another sheet of TMX with a sheet of diffusion mylar in between, and develop that in a very soft developer to create a
subtle unsharp mask. It's simple in principle, but there is quite a bit to doing it precisely. Like all such things, you want to start with a carefully exposed master negative of something like a MacBeath Color Checker Chart, with an integral gray scale. You don't need special
registration gear just to begin learning the basics; but it comes in awfully handy if you're going to do much of this. If you are seriously interested I could be more specific. Part of trick is the developer. For the second sheet I use a very dilute tweak of HC-110 (1:31) with a
bit of benzotriazole added as a toe cutter. It's one of the very few combinations which will yield a very low gamma long straight line.
FP4 is another film which can be used, but it's not quite fine-grained enough for contact work with small negs. Fine for large format, however. The final sheet film mask is then taped to the original for printing. In the case of 35mm, you obviously need to trim this down.

 

[fdonadio]

If you are seriously interested I could be more specific.

I am very seriously interested, for sure.

But, for now, I am gonna read more on unsharp masking. My lab technique is still very poor and I need to improve my enlarging skills a lot.

Thank you very much for all the help. I'm taking notes of everything you said and, I hope, will get back to them soon.

 

[Mainecoonmaniac]

Good job

Do not use a cine film. You will have a contrast mismatch.

See the reference above for my method.

Here is an example made on Portra from an Ektachrome slide.

PE

It's beautiful. Most internegs I do gain contrast.

 

[Photo Engineer]

The pull process does the job as suggested by EK. Although Kodachrome is a problem.

Thanks.

PE

 

[DREW WILEY]

I'll admit my approach to Kodachrome was a bit involved; but it killed two birds with one stone. Here again I made a contrast and hue controlled printing master via projection onto 8x10 dupe film (but more like 5x7 actual size, in the same proportion as 35mm), which would
hold saturation in larger scale printing. This also allowed visual evaluation of the result on a lightbox. Then from this to a contact interneg. My favorite dupe film ever was Astia 100F. It would do an excellent job of replicating difficult Kodachrome and Velvia hues, then transferring these to a secondary medium like Portra. But if you tried it in one step, there would be a lot of "lost in translation" issues. But it takes awhile to calibrate everything correctly.

 

[Mainecoonmaniac]

It's brilliant

The pull process does the job as suggested by EK. Although Kodachrome is a problem.

Thanks.

PE

Is it just as good as the old Kodak Vericolor interneg film? I think the old interneg film was tungsten balanced. When you pull the film, do you also have to lower the ASA?

 

[Photo Engineer]

On easel there is really no ASA due to the lighting and exposure times involved (reciprocity). You see my scan of an internegative above. It is pretty good but not as good as the old interneg. It is what we have and the system works well enough. You want to go all digital? That is the alternative!

PE

 

[DREW WILEY]

I haven't experienced any reciprocity issues with Portra 160 as long as standardize in my usual 10 to 20 sec range, and enlarger exposure is no issue either with a minor bit of colorhead tweaking. Astia also worked superbly for slightly long tungsten exposures. I still have some of this left, but overall, using multiple sheets of 8x10 film is just getting too expensive. I'm saving some of my stash for dye transfer printing; but otherwise, I've got enough color neg originals to keep me busy till I croak, and will probably convert only a very limited number of chromes to internegs. Even getting another C41 sheet film run back today. We adapt.

 

[Mainecoonmaniac]

Thanks PE!

On easel there is really no ASA due to the lighting and exposure times involved (reciprocity). You see my scan of an internegative above. It is pretty good but not as good as the old interneg. It is what we have and the system works well enough. You want to go all digital? That is the alternative!

PE

Thanks for the tips. Yep, we have to work with what we have. I think for slides, I might go the digital route for a few transparencies. But for large jobs, I might dupe it on to film.

 

[Wayne]

How does one calculate exposure of internegs? I hope the answer isn't lots of expensive trial and error.