Simulating Alternative Processes with Cross Rendered Proofing

Summary: This article describes the use of Cross Rendered Proofing techniques in the domain of simulating traditional alternative photographic printmaking techniques, such as Albumen prints. We provide profiles for you to try this for yourself for Albumen, Van Dyke Brown and Cyanotype prints.

The same technique could be extended to any number of alternative process, such as Photogravure, or Bleach Bypass (which we plan to do in the future!)

Contents

Introduction

Recently I helped with an interesting project, on behalf of RMIT student Boheme Jennifer Rawoteea for her final year research project. The project's goal was to use modern digital techniques to simulate a traditional, alternative photographic process.

Boheme chose to attempt to emulate Albumen prints. These prints have a unique character of warm eggshell tones, and compressed tonal range - with dense shadows and creamy highlights. You can read about, and see examples of, Albumen prints on Wikipedia or a much longer and better site here. Albumen prints are today still made in the way sketched out on Wikipedia - cotton rag papers are used, and the result is a rich print with a slight texture and slight glossy appearance from the egg wash.

Boheme brought some sample prints to our office and immediately I noticed that the substrate/slight gloss effect of the prints was very similar visually to prints made on Hahnemuhle Photo Rag Satin paper.

We decided to use Cross Rendered Proofing as the process for simulating the original albumen prints with prints on Photo Rag Satin. While there are other techniques for simulating film based processes (see an article I wrote several years ago, for example), these techniques all involve judging the process by eye and extensive work in Photoshop to achieve the look that is unique to the process in question. In my experience, this is generally a significant amount of work, and often the results are good but just not quite perfect.

Why simulate a traditional process? Why not just use the traditional technique?

There are many reasons to simulate traditional processes, rathen than actually print with the traditional process itself.

Firstly, not everyone has access to the materials required for many of the processes, and many alternative processes use chemicals that can be quite unpleasant to work with (at times even unsafe!). Of course it's often quite possible to work safely with most of the chemicals involved in most alternative processes, however in my experience this is a concern for many people.

Further, it can take significant time to develop the skills required to make high quality prints with alternative processes (there are 6 month fill time courses on alternative processes on offer, so it's not exaclty something you can master in a few hours one Sunday afternoon!). Obviously good digital technique takes just as long to develop as good analogue technique, but I assume most of the people reading this article are already quite good with digital imaging and comfortable with the use of ICC profiles.

Use of these techniques allows you to:

Using Cross Rendered Proofing to simulate an alternative process

By using Cross Rendered Proofing, we can take direct measurements of the important characteristics of the original prints directly, the result being a very quick, very effective simulation of a particular print process.

As you can see from the article on Cross Rendered Proofing, three things are required:

  1. A properly calibrated high quality monitor (for initial soft proofing on screen)
  2. Accurate knowledge of the final printing process (in the form of a measured ICC profile)
  3. A properly profiled inkjet printer using paper stock that is a good match for the final output stock

Numbers 1 and 3 are easy - we already have excellent screens, properly calibrated, and we have already created excellent custom profiles for Photo Rag Satin printed on our Epson 7800.

Step 2 is the key to the process - we must create an accurate description of the Albumen print in the form of an ICC profile. This profile must reflect the tonal qualities of the print as accurately as possible - essentially the colours and densities of the tones from d-max to d-min (maximum black to paper white, basically).

ICC Profiling of Albumen Prints

To create an ICC profile for Albumen prints was in fact relatively simple - we simply adapted our regular profile making techniques for black and white prints (Albumen prints, while toned, are of course a mono-chromatic print process).

However, we needed the profile target to be printed as an albumen print. This invloved the creation of a digital negative for contact printing. Essentially, our black and white target was inverted and printed on clear film. Attention was paid to getting the tonal separation correct on this target print.

The basic process is to use an inkjet printer to print to clear film. Ideally an ICC profile of the clear film is used so that the resulting negative print has good, linear tonal separation. It is important to remember to invert the profile target image when making this print as the final print will invert the image again back to its original form, which is what the profiling machine is expecting.

The digital negative was then printed as an albumen print by Ellie Young.

We then read the Albumen print in using our spectrophotometer and created an RGB profile of the Albumen print process. (You can download this profile to inspect (or use for yourself) in zipped form by clicking here). The spectrophotometer recorded that the albumen print process shows some solarisation in the shadow tones - the data was massaged slightly to remove this solarisation while maintaining the general tonal response curve of the process.

The result is a very accurate ICC profile that describes the Albumen process.

Putting it all together and making a print

A black and white image is opened in Photoshop and we proof with the ICC profile for Albumen prints:

Albumen ICC Profile Soft Proof

Here you can see we are doing an advanced soft proof of an albumen print (notes on this process here) . In the right hand corner you can see the original black and white file.

At this stage, with the soft proof on, we can edit our image to take best advatage of the available tonal range of the Albumen process. For example I slightly increased the contrast of the image above to to take better advantage of the limited tonal range of the Albumen process.

To make the print, we set up a Cross Rendered Proof:

Albumen Printing With Cross Rendered Proof

You can see that we've used 'Proof' as the print rather than 'Document'. We've let Photoshop determine the colours and chosen our profile for the paper stock we're using (Photo Rag Satin). We've made sure to tick 'Simulate Paper Colour' and 'Simulate Ink Black'.

If we now hit print, we should get a very accurate simulation of an albumen print.

The Results

The results are, put simply, uncanny - the digital prints are an excellent match to the original albumen prints. The tonal range is spot on (not surprising as it's been accurately measured with a spectrophotometer) and the tonal character is uncannily accurate as well. To be honest I was suprised at just how succesful the process was! The accuracy far exceeds any ad hoc techniques I've seen applied in Photoshop for simulating alternative processes.

It helps a lot that Photo Rag Satin has a very similar visual character to the prints Ellie Young made using the albumen process. Photo Rag Satin is an unusual paper with limited uses in my experience, but was perfect for this project. Hahnemuhle produce a number of papers with the Satin coating, so other options are available.

It's worth noting this process only helps you simulate the tonality of the process you are simulating. Paper characteristics are hopefully achieved by choosing a very similar output stock to that which is traditionally used with the process.If there are other physical characteristics - such as grain structure, embossing stamps, or irregularties from hand coating etc, then you will still have to re-create this in Photoshop with other techniques (such as texture overlays) if they don't come from, say, your scanning process (a good scanner used properly to create a big beautiful file should capture the film's grain structure very well - we can help with this).

Summary of what's needed to do this for ANY print process

Want to learn about real alternative processes?

Australia, and particularly Victoria, is blessed with several excellent teaching insitutions where you can learn about traditional printmaking processes.

Of course there are some excellent online resources as well - as ever Google is your friend!

Profiles to download