Mix of Spirulina (Spirulina platensis) and Turmeric (Curcuma longa) anthotype by Mariam Matta

“Free Roaming Friends” by Mariam Matta, Los Angeles, California, USA
Parts used: Powders
Amount: First, equal amounts of both powders, then I added slightly more turmeric. Minimum triple liquid to powder ratio by volume for solvent
Extracted by: Soaking and swirling in a metal cocktail shaker, then draining slowly through coffee filters.
Solvent: 91% isopropyl alcohol, and a tiny bit of water for getting the stubborn bits drained
Application: Airbrushed until the paper was evenly a deep yellow

Substrate: Canson XL watercolour paper, the smooth side
Created with: Two colour inkjet positives together, printed on cheap Weliu transparency film with an Epson ET8550
Exposure: 1 hour using UV lamp, October, early fall 2025
UV strength: Used a 30W UV lamp mounted parallel a few inches away from the paper. A UV meter indicated UV dosage accumulated at roughly 75 mJ/minute at this distance
Contrast: ✿✿ (Medium)
Challenges or observations: I began airbrushing this emulsion because brushing an even coat with an alcohol-based solution was nearly impossible. The emulsion performs best with a higher alcohol content, and airbrushing made a world of difference. Sharper results can be achieved on thinner papers like smooth watercolour or matte heavyweight inkjet papers, though the smooth side of Canson XL handles the moisture from toning washes well without warping. The toning solution – a mix of baking soda, washing soda, and water – was also airbrushed on after exposure.
Additional information: I applied the emulsion with my airbrush, double-straining it to prevent clogs and spraying at half power from arm’s length. It uses a bit more emulsion and needs thorough cleaning, but the smooth results were worth it. I now use a cheaper airbrush with a larger nozzle for toning. I bonded deeply with this curious peacock and white emu at a free-roam wildlife sanctuary in the desert. This print is an homage to them. The peacock was perched on the patio sofa, peering through our cabin window, which explains the image’s lower contrast.
Instagram: @vibefae
Bluesky: @vibefae.bsky.social
Website: mariammatta.univer.se