View Full Version : Do you need to use inter-negative to use slides in darkroom?

17-Sep-2011, 00:52
Do you need to transfer slides to inter-negative film to use them in the darkroom?

Some assistant teacher told me this, when i asked. But i don't believe so because i've seen people using slides directly and places in the enlarger that fits slides.

Anyone know?

17-Sep-2011, 02:04
There's only Ilfochrome left for printing colour slides, it's expensive and not the easiest of processes. There was special Internegative films but they are long discontinued.

You can still make an interneg on C41 film then print RA4 but most labs now scan and print digitally, or scan and print with a Lambada printer.


Greg Lockrey
17-Sep-2011, 08:25
Back in the olden days when you could print directly on reversal paper, using internegs was still better. We used to make masks and control the contrast and cool stuff like that too. Slide film was the "last" way you wanted to photograph something if the end result was going to be a print. It was the easiest to process in order to see a result however.

17-Sep-2011, 09:15
You can print directly from slides using Ilfochrome: the results are excellent but the price is very high. Contrast control is a real issue. You often need a contrast mask, making the process less than optimal for 35mm.

Try enlarging the slide onto LF film and then contacting the resulting negative.

Ivan J. Eberle
17-Sep-2011, 09:42
Well, that advice is a bit long in the tooth but an interneg is going to be the only way to get wet darkroom B+W prints from color transparencies these days. And if you're doing many copies of a color print from the same transparency, it may be a lot faster and certainly cheaper to use RA4 than Ilfochrome (and cheaper than the media costs of digital prints on an Epson btw).

But if you go this route today you're going to need to improvise some. I know Fuji doesn't make interneg film anymore and was recommending Pro 160S. Terrific emulsion, Kodak Portra NC would work almost as well (but for having somewhat larger grain) if you can yet find some. These are daylight color-balanced films, so you'd need to use it with electronic flash (preferably diffused) or actual daylight if duping with it instead of a tungsten source (which is what most of the interneg films and duping devices using enlarger heads were).

Daniel Stone
17-Sep-2011, 16:14
160NC was recommended to me by a former professor for making enlarged internegatives(35mm-->4x5 film), and the results turned out great! Some people also used to do enlarged transparencies(say, 35mm--> 4x5) for doing BIG enlargements(like murals) before lenses designed especially for big enlargements from the original(35mm) film were brought to market, much in line with say, the modern, "Rodagon-G" enlarging lenses.

I've done enlarged color and b/w internegatives, and it takes some getting used to. Getting a "system" down is important if you plan on doing it a lot, and getting color balance down(since most enlargers have tungsten/halogen bulbs, not daylight(~5500-6000k) light sources.

Astia(now discontinued supposedly :( ), was the preferred film for enlarged chrome dupes for analog-only people. I used expired E-Dupe when I do/did it, so I have no experience with that method and Astia, just what I've read here and other sources.


17-Sep-2011, 16:42
do dirrect reversal on the paper---works just like film---I've done it and it ain't hard----

expose the slide on REGULAR paper...develop till done...wash out the developer...then bleach it with dichromate bleach till the image disappears...TURN ON THE LIGHTS....use some clearing bath to help wash out the dichromate--then RE-develop it....you get a reversal--I do this direct from the camera with paper.

19-Sep-2011, 06:50
You can do a direct reversal on the RA-4 paper. I used to do it in the past. Color will be petty off and I tried fix it to certain degree with filter on second print. If you are interested, you can google RR-4 Process. The process name is given by some who initially did the experiment on the paper.

Drew Wiley
19-Sep-2011, 08:59
I would imagine one of the new Portra films would work decently as an interneg. I did
some experiments with the previous generations of Portra and got decent results, though for really high quality work some masking correction would generally be needed,
but's that's true for Ciba too. It's largely just a matter of correcting the color temp
balance. You might have some trouble with translating Velvia onto an interneg without
masking. Generally I found Portra to work better than the older official Interneg films.
Just takes some practice and the right equip, just like anything else.

Daniel Stone
19-Sep-2011, 10:46
the interneg films of yore were tungsten balanced, IIRC. So the only color filtration you'd have to do would be if your original transparency was off color, say, too cool.


Mark Sampson
19-Sep-2011, 11:04
Not to drag up ancient history here, but the Kodak internegative films were extremely sensitive to the color of exposure light, and had to be carefully tested and color-balanced to get anything like accurate results. I've used them all from the days of the "C-22I" process c.1980, and with any of them, if you got it wrong your results would be just plain awful. Their last film, #4325, was the best by far but it's been gone for 5 years at least. All the I-neg films were slower, finer-grained, and much lower in contrast than any contemporary camera color-negative films, so my hat is off to anyone who can make good internegs with Portra.

Drew Wiley
19-Sep-2011, 11:32
Well Mark, it certainly seemed straightforward. But then I guess I'd be classified as
someone with advanced masking skills who does that kind of thing almost without thinking about it. Don't know if I'll experiment much more on the interneg theme
however, since I primarily print C-prints directly from negs (sometimes masked) and
still reserve chromes for Ciba or more rarely for DT. Where there's a will, there's a way.
What I will miss the most is Astia 100F sheet film for positive dupe use, which was
superior to official dupe film by either Fuji or Kodak.