Oregon grape (Mahonia aquifolium) anthotype by Bernd Hutschenreuther

“Mahonia aquifolium” by Bernd Hutschenreuther, Dresden, Germany
Parts used: The dark blue lilac berries
Amount: 5 berries, for a print 10×15 cm
Extracted by: Mashed with a teaspoon in alcohol
Thinner: 5 mL of isopropyl for one image
Application: Brushing

Layers: 4 thin layers
Substrate: Glossy photo paper for inkjet printers, 10x15cm
Created with: Photogram of an Oregon grape leaf
Exposure: 4 hours under a UV LED spotlight, August, summer 2025
UV strength: LED Spotlight (100W equivalent)
Temperature: 22° Celsius (at the beginning)
Humidity: 19% (at the beginning)
Contrast: ✿✿ (Medium)
Challenges or observations: The sun was nearly absent over the past few days, so it took three full days to expose a single image using sunlight. The subject was a photogram of an Oregon grape leaf. I observed an interesting effect when using UV light: the image developed a blue tone in dry areas, while areas where water had evaporated during exposure turned violet. This seems to be caused by the type of paper I used — glossy photo paper made for printers, which appears to be alkaline. It likely acts as a pH indicator: in dry areas it stays blue (alkaline), but where the leaf releases moisture, the emulsion becomes more neutral or slightly acidic, resulting in a lilac hue. For the final image, I used UV LED light.
Additional information: Oregon grape berries are mildly toxic and not considered suitable for children, according to Wikipedia. However, they are still technically edible. I handled them with care during the anthotype process. The plant is also known by another name: Holly-leaved barberry.
Instagram: @hutschinetto
Website: https://www.flickr.com/photos/116228447@N06/