Temporary Note: until I check the links on these pages, it may be easier to use the back button to move back to this list after going to any of these pages.
Technical Notes
General
Myth: Gum can't express fine detail
Myth: Gum prints are coarse and lacking in subtle tonal gradation
Myth: pigments in gum emulsion act as color filters that differentially block UV
Gum and humidity
Materials and Equipment
Gum Arabic
Dichromate-- issues in selecting dichromate type and concentration
Pigments (in the form of watercolor paints)
Issues in determining pigment concentration
Transparency and Opacity
Myth: Chromium pigments are incompatible with the gum process
Paper
Negative
Paper negatives
Light Source
Miscellaneous supplies and materials
Mechanism of the process
Simple explanation of the process
Technical discussion of the chemical mechanism
Myth: The chemistry of gum is the same as the chemistry of chrome tanning of leather
Tricolor gum
Myth: you can't produce black using three colors; you need black pigment too
How RGB channels become CMY separations when inverted
Why the default Photoshop CMYK option may not be the best choice for separations
Stain
Pigment Stain
Myth: Pigment stain is a function of underexposure
"Tonal Inversion" as a subset of pigment stain
Dichromate Stain
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