This is the Picture ke Peeche info for the Motif image I posted on Monthly Theme.
I took this using a 100mm Macro lens wide open at f2. As you can see, as I kept de-focusing the subject, strong patterns started emerging. I experimented with the angle and de-focus and settled down on the one I shared. I do not know the science behind this: is it to do with the optics of the lens? Is it light playing tricks? Or something else? No idea.
If you can throw any light (pun intended) on this effect, please share.
Regards,
Ramesh
PS: I'm not able to add an image here at present. Please follow this link for the reference image: https://www.flickr.com/photos/ramesh_adkoli/32511983357