I used to be the ultimate celebrity spotter. I have what I call radar, and yes, it is a 6th sense about the impending presence of a celebrity that has won over many skeptics. I can spot a celebrity from at least a block off. It’s a skill. Recently I have questioned whether my radar was losing its power. I haven’t spotted a celebrity in many moons. (I chalk this up to the fact that I live on the Upper East Side of Manhattan and honestly, most celebrities, aside from the truly patrician or aged, live downtown or even in Brooklyn these days.) However, just now, on my street, I spotted an Olsen. I believe her to be Ashley. She probably just came from…