I wear glasses as well and find the older rangefinders a bit tricky, nonetheless, I still enjoy them. The Nikon SP is a nice camera to have in the collection. Giving students the chance to shoot with K1000 is a great start. I've always thought that relationship between if I change the aperture setting, then I'll need to change the shutter speed too to retain my exposure, was an intuitive way to learn. I've never heard "P" standing for "Professional" I always thought, and trying to remember where I first learned it, that it was for "Program."