Van Dyke Brown
Van Dyke Brown is an iron-silver alt-process producing rich warm-brown prints through a single-bath sensitizer (ferric ammonium citrate + tartaric acid + silver nitrate) coated on paper, exposed under UV, and developed in water. Van Dyke (named for the painter Anthony van Dyck) was published in the late 19th century and remains popular among alt-process printers for its warm-brown tonality, simple workflow, and accessible chemistry.
Key features
- Iron-silver chemistry — combines iron sensitizer (light-sensitive) with silver salt (image-forming)
- Warm-brown image color — distinctive sepia-like tonality
- Single-coating workflow similar to cyanotype
- UV exposure under digital negative or contact print
- Modest archival permanence — gold or selenium toning recommended for fine prints
Workflow
- Mix sensitizer: ferric ammonium citrate + tartaric acid + silver nitrate dissolved in distilled water
- Coat paper in subdued light using brush, hake, or rod-coater; dry in dark
- Expose through digital negative under UV light (10-30 min depending on density)
- Wash in plain water (image emerges as wash proceeds)
- Fix in dilute sodium thiosulfate (5%) for 1-2 min to remove unexposed silver
- Tone optional: gold toning improves permanence and shifts color slightly cool
- Final wash 30+ min running water
Practical notes
- Use distilled water for sensitizer mixing — tap minerals interfere
- Choose papers without sizing (pre-calendared watercolor paper works well)
- The fix step is required to prevent slow image fade (unfixed Van Dyke gradually loses density over weeks)
- Compatible with multiple coatings for higher density
- Light-sensitive during coating and drying — work in subdued non-UV light
- PPE: nitrile gloves; silver nitrate stains skin black (harmless but persistent for days)
Related recipes
- [[recipe-classic-cyanotype|Classic Cyanotype]] — alternative iron-only alt-process (no silver, blue color)
- [[recipe-new-cyanotype-ware|New Cyanotype (Ware)]] — modern improved cyanotype
- [[recipe-platinum-palladium|Platinum/Palladium Print]] — premium alt-process alternative
- [[recipe-gold-toner-gp-1|Gold Toner (GP-1)]] — recommended permanence-enhancing post-treatment
Mixing Instructions
Solution A: Dissolve 90 g ferric ammonium citrate (green) in 330 ml distilled water at 20 °C.
Solution B: Dissolve 15 g tartaric acid in 330 ml distilled water.
Solution C: Dissolve 38 g silver nitrate in 330 ml distilled water.
Combined sensitizer: Mix A, B, and C together. Store in a brown glass bottle away from light. The combined sensitizer keeps for several weeks.
To print:
- Coat onto paper under dim incandescent light with a brush or glass rod.
- Dry in the dark.
- Expose under UV light.
- Develop in running water.
- Fix in a weak sodium thiosulfate solution (2%) for 2 minutes.
- Wash for 15 minutes.
Ingredients for 1L of Working Solution
| # | Chemical | Role | Qty (1L) | Unit | Note |
|---|---|---|---|---|---|
| 1 | Ferric Ammonium Citrate | Toner | 270.0 | g | |
| 2 | Tartaric Acid | Other | 45.0 | g | |
| 3 | Silver Nitrate | Sensitizer | 120.0 | g |