Colors may be helpful indicators, but they are very limited in their suitability for determining a process. Since it is difficult to determine fine variances of eye and to put them into words, only coarse shades are available here. Glass images should be viewed in bright light to clearly see the tonal values (avoid reflections).

Blue: In photographs on paper, blue tones are a dominant feature of cyanotypes. Pigment prints can also be blue if a blue pigment is used.

Other colors: «Different colors» refers to photographs that have different colors than those available for selection.

Colored: Colored pictures were painted by hand. (Attention: do not confuse with colour photos or multi-coloured glass pictures!