This not a typical post. This time it’s not art but photographs, albeit slightly blurred, which in this case was a good thing! I had not originally intended to include straight photos in this blog. (I have another place for that), but there are a few, since one of my aims is to get people to really look at things which they might not have noticed before.
This is a closeup of part of a spider web, caught in just the right light to show a Thin Film Interference (TFI) light effect on the strands. This is what a spider web contains! Or rather, this is what your eyes may see if you are lucky enough to catch a web in front of a dark background, like the shaded woodland here, but against the light. The colours which we see are not “what is”, but rather what is produced through the combination of our eyes’ lenses, the available light, the position, the background, the materials, the distance etc.
This spiderweb effect may be due to Thin Film Interference, the same thing that produces colours in soap bubbles or films of oil or gas on a road, or it may be Diffraction. Opinions differ and the physics of it all is beyond me!
According to Wikipedia, Richard Feynman has said,
BTW, the circles in the above photo (possibly what some people call “orbs”) are likely dust particles, as they catch the light.
Something similar can also be seen sometimes on close-ups of dandelion spokes, probably not very visible in the small photo below. The iridescence of some bird’s feathers, beetles etc., is another closely connected effect. If you want to know more, check out TFI and Diffraction on the web.
