Heather Siple experiments with anthotypes to find out which impact different types of paper base has on the color of the plant emulsion and how to choose papers for antotypes.

When I first found out about anthotypes a few months ago, I was intrigued. I had to try my own experiments! I read everything I could find online one afternoon while waiting for Malin Fabbri’s book Anthotypes – Explore the darkroom in your garden and make photographs using plants to arrive in my mailbox, and dove into the refrigerator to find veggies to mash. But, the only paper I had on hand were a few sheets of 90 lb. drawing paper. So, I decided to try what I had on hand, just to see if I could get any picture at all before buying the aquarelle that most people were using. I found the paper took the dye nicely and provided a nice, smooth finish, so I continued to use it along with aquarelle for my printing. This lead to an interesting discovery: Many plants produce different colors from the same batch of emulsion on different papers!
The first time this showed up was when using dark, purple pansy (viola wittrockiana). I had seen a beautiful purple shades in Fabbri’s book, yet my own dark, purple liquid turned into a blue and green print.
I began running tests on my new emulsion batches, making test strips and prints from Strathmore 140 lb watercolor/aquarelle cold press paper, Canson’s Bristol 96 lb acid-free recycled paper, and a few tests with Strathmore 70 lb acid-free drawing paper (later abandoned because this paper is just too thin). The plants tested so far are pansies, their cousin’s common blue violets (viola sororia), common buttercups (ranunculus acris), eastern redbud (cercis canadensis), red azaleas (rhododendron ‘Christina Marie’ (Girard)), american wisteria (wisteria frutescens), Coral Bells (Heuchera sanguinea)and crab apple blossoms (malus sp.). I coated each paper with the same number of coats, at the same time, with the same camel hairbrush, from the same batch of plant juice. The redbud and apple blossom prints were done side-by-side in a contact printing frame. All prints comparisons were exposed for the same amount of time.
The result of different paper and base for anthotypes
As you can see, the differences in some cases are striking! Only the buttercup emulsion was left relatively unchanged between watercolor and bristol papers. The apple blossom was changed marginally. The rest had a very distinct color shift between papers. The most dramatic change occurred with eastern redbud, which ranged from lavender to pink to green!









I wonder if the cause of the color shifts are due to the pH/buffers in the papers you’ve used?
A lot of plant dyes are very pH sensitive and a shift in pH value can cause a color change. I believe the Straithmore paper is pH buffered as opposed to the Bristol that as far as I can see is just acid free.
It’s certainly something I’ll be trying to look into over the summer if I can gather enough plant material to try out.