A ventilator plate, but then inverted and blended with the original using a gradient.
It shows the typical 'eye flash' at intersections. On the white portion at the top it's seen as flickering grayish dots; on the black, yellow-white. And you can't stop those from just randomly firing all over the place.
In other words, the dots - at any resolution (particular over the black lines) - are present and part of the photo as far as the viewer is concerned. But in reality, the dots are not there. No matter how hard you try, you cannot see the photo as it actually is. Or, one could argue, that what it actually is - is what you see. You see the photo, then you see what is added before it reaches your conscious mind. All of that, in all cases, is 'the photo', no matter what you are looking at.
Thank you. When I was younger, I was interested in these sort of illusions, museum of science stuff. And you get this effect with most any grate or cover that looks like this.
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