View Full Version : Coloring digital negatives

Petzval Paul
5-Jan-2017, 15:10
Hi everyone, I just started trying to create a digital negative for the first time. Using photoshop on a Mac (am older version, CS3), I went through the usual protocol as I've understood it and everything worked pretty well, but there's one thing I'm not understanding. Using the 'fill' function at a relatively low opacity (10 or 15 percent) in order to colorize my negative (in an auburn tone) results in blocked up shadows - in other words, the parts of the negative that should be clear are also colored in a very light shade. Moreover, the highlights seem to take on color as well. Ideally, I would think that clear shadows and at least some black in the highlights.

With a lot of contrast control via the curves I was able to get a decent negative, but it took a lot of work. Ideally, I wound want my negative to look something like the one in this video: https://www.youtube.com/shared?ci=J3v4M0duCBI
Can anyone point me in the right direction?

Thanks, Paul

6-Jan-2017, 02:11
A fill layer will overlay a fixed density color over the entire image, independent of the actual image information. A proportional coloration can be obtained in several ways, e.g. by setting the layer style to 'overlay', by using the channel mixer or through the 'colorize' command. Another method, which is the one that I exclusively use, is to assign a particular tone through the printer dialog. This works well with Epson printer drivers; not sure about other brands.

Other than that, digital negatives require extensive calibration for every process used, but you probably already knew this. On the upside: when properly calibrated for your process parameters, you can print any image and get a decent result in one go.

Petzval Paul
6-Jan-2017, 13:51
Thank you very much that useful info. I have actually enjoyed the calibration stages so far - reminds me a bit of being in the darkroom. I'm going to get back at it using the process you have suggested and see what I can come up with. Thanks again!

7-Jan-2017, 05:52
You're very welcome, I hope it helps! Yes, the calibration stage can be fun - although it tends to get a bit boring when you're calibrating for the third or fourth workflow ;) on the upside: it gets easier every time. The other day I recalibrated my photopolymer intaglio workflow for my new light source and I was able to nail it down (reasonably well...) within a couple of tries.

Michael Rosenberg
7-Jan-2017, 13:44
You can take a look at my monograph on my web site to get an idea of how to go through the calibration and curve creation process: http://www.mprosenberg.com/digital-negatives

You did not say if you were trying to do silver gelatin or alt process.


Petzval Paul
10-Jan-2017, 10:19
Thanks so much for the link, I will check that out right now. I really only ever print in cyanotype or gum, silver gelatin contact printing only very rarely. I gave my enlarger to a friend whose teenage son was interested in shooting film. I think that he's in art school now ��
I tired the colonization technique that you mentioned and it worked really well. I hope to print up my test negatives once the weather improves later this week, as I am using the sun as my light source.