The Amazon.com shopping screen filters have a missing item when searching for camera lenses: no “Prime”1. You can’t search by prime lens. (i.e., those lenses that aren’t “zoom”.) Any lens that has only one focal length is a prime lens. Some prime lenses are also called “wide angle” and “fisheye” and “macro”, but they are prime only if they have a fixed focal length.
It’s interesting that you can’t filter in this fashion. I assume, knowing nothing really, that this is because no one has asked for it. This further leads me to assume that most people who search on Amazon for camera lenses are interested in zoom lenses, or macro lenses, or wide-angle lenses, and not in the bread-and-butter prime lenses. I will go even further out on my dangerous limb and conclude that the audience for this site primarily consists of people who don’t know much about the ins and outs of SLR lenses.
There. I’m being photo-elitist!
Actually, we can probably make the same assumption just based on numbers. A gazillion2 cameras are sold every year, but there is a much smaller number3 of photographers who really get into the gear. An observation that only gear-heads and serious photogs buy the good prime lenses leads me to the conclusion that Amazon primarily sells zoom lenses and other “interesting” lenses, mainly.
Or, I could just be making this all up4 and talking out of my butt.
Still, it’s an interesting omission from the filters.