What I call “Overlays” start out the same as my mirror images: a second copy of the image is flipped. However, this time, instead of butting two edges together, the two overlap. An example from back in the day, if you had two identical 35mm color slides (if you know what those are…) flipped one and then sandwiched them to together. It would take a very strong light from behind to illuminate them, but the results can be fascinating.
Light passing through two different colors produce very different color combinations from those we are familiar with, whether it be crayons or paint. We see “subtractive” pigment based color, for example from paint, by light reflecting off of it. Color produced by transmitting light through something transparent, such as a 35mm slide or a stained glass window is “additive” color.
We learned as children that mixing red and yellow crayons (subtractive colors) results in orange. Yet surprise, surprise, when we mix red and yellow light together we get (wait for it…) green! While green and blue make cyan! These results don’t always occur with things like glass, because they are usually a mix of several colors. But the computer monitor is pure red, green and blue with dramatic results.
You can see why the results of my “Overlay” images are so very colorful and so very different from the original photo. I find the results to usually be a surprise and a lot of fun!