Air bubbles during the developing phase of bichromate gum result in dark stain on the print.

Use a threading bar to quickly and evenly size paper sheets for historical processes.

The addition of tartaric acid in VDB solutions reduce the quantity of precipitate.

Preparation of classical VDB solution and modified (without precipitate) VDB solution.

Dupont 4-R intensify shadows and reduce high densities to correct exceptionally contrasted analogical negatives.

Influence of basicity on the color of Cyanotype: the results using cheap and slightly basic paper are visually superior.

A special tea toned posterized cyanotype print.

Bristol 350g: low-cost, deep shadows, high weight, fine detail for cyanotype.