There’s an old technique in chemical photography for making etching-like images. You sandwich a negative and a positive of the same image together just slightly out of register, and print the whole thing on lith film, then you make your print from the lith.
I thought I’d see what happened to an image of mine with that treatment. With my darkroom turned into a storage area, I turned to Photoshop. I converted the image to B&W, duplicated the result as another layer, and set the blend mode to difference. I zoomed in, and moved the top image a tiny bit. Then I added a Levels layer on top and moved the white point way down. That got fiddly, so I added another Levels layer and did the same thing. Then I zoomed out to see what the whole image looked like.
Blackness.
I zoomed in. The image came back. I zoomed out again. Nothing but black. I wrote out the file, brought it into Lightroom, and it looked fine. Closing Ps and reopening the image showed approximately the right thing, but much darker than the Lr presentation, and darker than a JPEG file exported from Lr.
Photoshop version 14.2.1 x64, if anyone wants to try and duplicate my experience. File size is 6764x4407. Display res is 2560x1600. Ps window was maximized.
A small JPEG of the image is
here.
Jim