Image processing, highlighting hidden details

[merrimacga]

I'm sorry that I have been too brief (as so often), leading to confusion.
In my plots, the bottom right corner of You are not allowed to view links. Register or Login to view. shows nothing, and that is not the area I meant.

The area I meant is below the central pool, but still above the bottom pool on the other side (f75v).

Just to clarify what I am saying: this process brings up structures, and many of these are already (partly) visible in the original image:
- folds and blemishes
- shine-through from whatever is on the other side of the same folio.
- In some cases also print-off from the opposing folio

Others are not so easily identified. The area below the central pool is just the very first example.
I am not saying that there's a face or a cloud bunny. Just that it is similar in style as some of the shine through.

On the same page (f75r) at the height of the central pool, one can see the elongated horizontal pool from f75v.
Also, on f75v, the entire structure in the top half of You are not allowed to view links. Register or Login to view. dominates the image.

This might help illustrate Rene's comments. Here are You are not allowed to view links. Register or Login to view. and You are not allowed to view links. Register or Login to view. for comparison (you might want to zoom this page or right click each image to open in a new tab so you can zoom in):

Top left You are not allowed to view links. Register or Login to view. from the Folio Browser. Top right You are not allowed to view links. Register or Login to view. from Rene's images.

Bottom left You are not allowed to view links. Register or Login to view. from the Folio Browser flipped horizontal. Bottom right You are not allowed to view links. Register or Login to view. from Rene's images flipped horizontal.

          

         

Weirdly, and unrelated, I noticed something else about You are not allowed to view links. Register or Login to view. (Folio Browser version). Cock your head to the left and tell me if you don't see what looks like diagonal handwriting. I realize it is just a trick of how the glyphs are lined up on the page and it probably doesn't mean anything. Weird.