Pareidolia, but underwater: What is under the green paint?

[Jorge_Stolfi]

This is very similar to what I tried last year, [...] The full gallery: You are not allowed to view links. Register or Login to view.

Thanks!  I think I am getting slightly better results for "invisible" ink.  For instance I get a stronger signal for something between the feet of that nymph, and maybe for something under the east end of the "backrest" she is leaning onto. We will see...