The circular disk with concentric circles, commonly seen in Turkey and Greece, are meant to ward off the "evil eye" - dirty looks that some cultures think can cause bad luck. If you would like more information about this, just do a search for evil eye on the Internet.
An older gentleman sitting alone in an outdoor café made an excellent photographic subject and I made a couple of images of him before he saw me. He was a local resident who was used to the climate because it was a hot morning and he was dressed in long pants and a long-sleeved jacket - certainly not the typical tourist garb.
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