Cuprea-Van Dyke

This is the marriage of two cousins: Uruduᵗᵘᵖᵉ and Van Dyke. Copper brings brightness to Van Dyke, and iron brings contrast to Uruduᵗᵘᵖᵉ. Depending on the percentage of copper, the image will be more or less bright, with 50/50 being a safe bet. Like Uruduᵗᵘᵖᵉ, I couldn't find any references, so I submitted a Soleau envelope (Stéphane Corbé, 2026).