[split] Jorge's Retracer Thread: darker ink, retracing of text and drawings

[Jorge_Stolfi]

As for the arguments to variation in ink shade, these can be just due to patchy/lumpy ink which may have also exaggerated over time due to different fading rate of different component of the original ink. I think I already posted an example of extremely spotty strokes from MSIs, here's another belowYou are not allowed to view links. Register or Login to view.. There are irregular dark spots, which to me obviously show that the ink was not some homogenous properly mixed substance. There were some darker blobs in it, and larges ones would be spread by the quill and lead to distinct patchy strokes.

Yes, one of the inks has those dark particles.  This is visible in one of the high-mag images from the McCrone report:
   
Such particles are not expected in fresh iron-gall ink.  Maybe they are lumps that form in ink after it is left standing for a while and oxidizes in the bottle.  Maybe they are droplets of some additive that separated out and lumped together as the ink dried.  

But maybe they are a black solid pigment, like coarse carbon black, that a Retracer added to a brown ink in an attempt to match the original ink color...

Note that some mottling is expected because the vellum surface is rough.  A translucent ink -- like the lighter ones in the image above (on the lower half of the right leg, and on the left leg) will collect in the dimples of the surface, and look darker there.   But the particles in your image, and in the darker ink above, are not that.

Frankly, I don't see how you can see images like the one above as evidence that Most of the Ink is Original...

All the best, --stolfi

PS.  You say you know the VMS as the palm of your hand.   Do you know about the visual gag of the transfolio nymphs in the Zodiac?