Carbon Surface View
Surface Sheen
A key identifying feature of carbon is differential gloss caused by the difference in surface sheen between the shadows and highlights due to a slight image relief; the gelatin is thicker in the shadows. While differential gloss is an identifying characteristic, it can be subtle and may not always be an effective way to identify carbon prints. In the double transfer process the temporary support could be polished or matte according to the desired surface of the final print.
A key identifying feature of carbon is differential gloss caused by the difference in surface sheen between the shadows and highlights due to a slight image relief; the gelatin is thicker in the shadows. While differential gloss is an identifying characteristic, it can be subtle and may not always be an effective way to identify carbon prints. In the double transfer process the temporary support could be polished or matte according to the desired surface of the final print.
What to look for: Differential gloss, a difference in surface sheen between the shadows and highlights. This is not always present however.
Examples of visible differential gloss.
This print does not exhibit differential gloss.
Surface Texture
Carbon prints are often on a support consisting of paper coated with gelatin. Therefore, the paper fibers will give the highlights a slight texture. The thickness of the pigmented gelatin in shadows will create a smoother surface. This results in a slight image relief which is seen as differential gloss using specular light. This can be subtle and may not always be an effective way to identify carbon prints.
Carbon prints are often on a support consisting of paper coated with gelatin. Therefore, the paper fibers will give the highlights a slight texture. The thickness of the pigmented gelatin in shadows will create a smoother surface. This results in a slight image relief which is seen as differential gloss using specular light. This can be subtle and may not always be an effective way to identify carbon prints.
What to look for: Slight paper fiber texture in the highlights. Slight image relief, usually noticeable as differential gloss (see Surface Sheen). This characteristic is not always visible however.
Paper fibers impart a slight texture to the highlights of the print. Carbon prints with a baryta layer will not have this characteristic.
Some prints have more heavily textured papers.