Color Control in Sepia Toning

I love sepia toning my prints, not only because it's an archival toning method but also because it can add very subtle color effects to enhance a print. I've been playing around with the level of color control that can be achieved and I'd like to share my results here.

I'd like to acknowledge some sources that were very helpful in learning the intricacies of sepia toning.

• Pictoral Planet - Easy Sepia Toning
• David Lingham - Sepia Toning
• DistPhoto - Sepia Toning
• Larry Bartlett -  B&W Photo Printing Workshop

I won't be discussing the preparation of stock solutions or toning process, as all of the resources above as well as countless other books and websites have that information readily available. This experiment uses Thiourea (Thiocarbamide) sepia toning solution, therefore the results will not be applicable to other types of toning solutions.

My first round of calculated mixing ratios, from 9+1 to 1+9.

Here are the results of the first sepia toning experiment, where I used the extreme ends of the mixing ratios to see what effect I'd get. These prints were all produced one after the other on Ilford MGRC Pearl paper. Resin-coated paper is difficult to tone, so the bleaching time was quite long on these. I do think the toned prints do give a good sense of the color variation possible. Below the toned prints is the original print. Click on any of the images to enlarge them.

Thiourea : NaOH

9+1           7+3           5+5           3+7           1+9

For the next test on fiber-based paper rather than splitting the toning ratios into 10 parts, for the sake of making measurements easier I decided to try splitting them into 5 parts. This made my ratios a bit simpler but less extreme: 3+3 being a neutral sepia, and the extremes at only 5+1.

My revised and final calculated mixing ratios.

This next set of prints was printed on expired Agfa Brovira Grade 3 Semi-Gloss paper, probably from sometime in the 1980s. This paper has been fun to use, and although it needs extended exposure times I've still gotten great results from it. The subject is a small section of a picture I took of gingko leaves; the final print that has since sold was sepia toned yellow to match the yellow color of the original gingko leaves.

Thiourea : NaOH

5+1            4+2            3+3            2+4            1+5

The fiber-based paper was much easier to bleach, therefore the toning color is much more obvious in the shadows and overall the color is much more rich. I don't usually bleach my prints to completion but since this is an experiment in toning, I let the prints go for about 5 minutes each until only the darkest shadows still remained. 

In a scenario where I'm producing an art print, I'll decide ahead of time what color I want to use and only bleach the print up to the point where I want to show the colors. In most cases this will mean bleaching the highlights but leaving the darker midtones and shadows unbleached. This gives a great mix of sepia color and rich shadows, which makes the prints much more 3-dimensional than a full bleach and tone.

In conclusion, I'm happy that I was able to show big differences in color when controlling the ratios of Thiourea and Sodium Hydroxide in sepia toning solutions. I think that working with the reduced ratio range (5 different mixes) gives most easily measured volumes and enough color control to fit most scenarios.

Thanks for reading! If you're interested in seeing more of my photography, please check out my Linktree.