12-11-2025, 01:41 PM
(12-11-2025, 12:16 PM)oshfdk wrote: You are not allowed to view links. Register or Login to view.The stroke is visible in IR with about the same intensity as in UV. So, it's likely this is not ink, maybe some dirt or some defect of the vellum.
According to You are not allowed to view links. Register or Login to view.,
Quote:Further, Fe is not only the main inorganic component of iron gall inks but also of ochre pigments, which were not only also used for underdrawing paintings but also often appear as pigments in paint layers. ... iron gall inks absorb IR radiation up to 1200 nm [You are not allowed to view links. Register or Login to view.] (p. 58) (Additional file You are not allowed to view links. Register or Login to view.: Suppl 2),You are not allowed to view links. Register or Login to view. while ochre already become transparent at 850 nm [You are not allowed to view links. Register or Login to view.] (p. 16).
Now people may want to have another look at those multispectral scans...
All the best, --stolfi

