I was thinking this morning that one of life’s greatest challenges is negotiating escalators, particularly down escalators, with bifocals. It is an issue of the age. It is a plain and simple issue of optics. There are all those parallel lines, metallic ridges, that seem almost intentionally designed to knock you off balance. I am always tentative about the first few steps and once I reach the first step of the right height, I just let kinesthetic memory click in. “Feets don’t fail me now!”
So this morning I thought that I would immortalize the subject with my IPhone. With the help of the “twirl” feature in Adobe Photoshop to replicate the psychological features, the result is shown in Figure 1. If you scroll up and down the image you should see a strobing of the image brought on by the phenomenon of aliasing. I remain proudly upright.