An experiment with false color...
Purpose of the experiment: increase visual contrast of source images, find traces of hard materials that could give structural hints of what we are looking at.
Goals: get as precise an idea of the shape of any hard objects located inside, but at, or very near the surface of stone.
Tools: - image editor. I'll use Gimp, an open source image editor, version 2.10.
Effects: 'Level' (Niveaux), uniquely modulating threshold and gamma.
The premises behind expected results Premises:
- Breakage, tear, or erosion of a structured object made of composite materials occurs at the weakest points. We thus should find 'bumps' of some of the hardest elements more or less intact at or near the surface of breaks and tears.
- During the mineralization process (fossilization) of a composite object, atoms and molecules of non-mineral material are being slowly expelled, creating a moving 'cloud' of matter around objects being mineralized. This is a very slow process. Nevertheless, this cloud of matter can create discolourations on the surface of stone, around, and in the general shape of objects at or near the surface.
(todo: I believe these basic premises are widely in use now, to say the least. This would eventually need the proper and presumably usual citations).
I call this technique 'the poor man's false color'. False coloring is not a new technique, and it is used quite often in archeology, and other sciences, to highlight features that are not immediately noticeable to the naked eye.
There have to be some specialized software to do this, if anyone could point me to an open source one, that would be great.
For now, I am lmited to what I have, so I'll use these simple tools: exposition (aka 'levels') and gammma. I've used Gimp for this, but this should be easily repeatable. Any decent image software should do.
We'll use this image for our first test. The area of interest is what looks like a beak, we'd like to see if there are any hints of articulations around the features highlighted with blue markings. We're trying to see how if there is an articulation around here, and for any hints of what it could be like. .
I've used these settings to increase contrast and focus around the region of interest. This is from Gimp, but these same settings can be used in any other capable software.
Keep in mind that the increased contrast will give us a sense of increased depth, that's how our eyes work. Still, this can potentially show us hints of the shape of any hard materials are at, or very near the surface of the stone. In other words, things are actually flatter than what they look with distorted lighting. I'm not equipped to flatten the appearance, nor is this absolutely necessary for exploration.
That's a very interesting result. I've highlighted again the zone I've tried to bring contrast and focus to:
This simple experiment can be repeated on any decent photograph of the colossi. It is very repeatable.
Source:
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indianvalleyscuba.files.wordpress.com/2012/09/p9131641.jpg