24-04-2026, 02:58 AM
(This post was last modified: 24-04-2026, 03:07 AM by Jorge_Stolfi.)
(23-04-2026, 08:30 PM)Aga Tentakulus wrote: You are not allowed to view links. Register or Login to view.The ink has penetrated deeply and can no longer be removed by rubbing or sanding.
I don't think that is what is happening in that image. Vellum is translucent, therefore even writing or paint that sits on the surface will be faintly visible from the other side.
And that is not just an UV image, it must be a composite with images at other wavelengths and/or transmitted light (backlighted) images. And possibly contrast-stretched to bring out the faint seethrough writing more clearly. Here is just the UV image with frontal illumination, with no contrast stretching:
Note that the writing on the back is only faintly visible. Instead what is very visible is the edge of the big water spill (A). And possibly the edge of the area where someone rubbed chemicals (B), like Wilfrid did at the bottom of f1r.
All the best, --stolfi