Linsday Robb posted a question yesterday about which lens to keep for a Pentax 645 manual out of a 120 macro and a 150. It was addressed to people who had both and answered well by several posters. I studied the question without experience with either, and bought only the 150, so I wasnt part of the audience to whom the question was addressed. For what its worth, I have been happy with the choice for the reasons the posters responded. That said, the question and responses brought some thoughts to mind that I didnt think were sufficiently responsive to post as a response, but I would like to share for comments. We all know that normal lenses get their label, at least in part, because their angle of coverage supposedly covers the same angle of view as the human eye. However, once upon a time, many, many years ago, in my 35mm days, I noticed that landscapes and travel images with normal lenses didnt really look the way I remembered the scenes. I discovered that lenses in the portrait range more nearly recorded what I thought I saw. I recall (hopefully with some accuracy) an article in a photo magazine by someone who studied paintings by the old masters of landscapes that are still basically unchanged today. The author went to the various sites and determined which focal length of lens (for 35mm) would record the apparent perspective that Gainsborough, Constable, or other artist had recorded in his oil. His conclusion, expressed in 35mm terms, was that their focal length was not the normal one, but rather 85 to 105. There is, of course, no greater confirmation than someone else, however studied, saying something that one already himself believes. Much more recently, in the computer era, I had my monitor refresh rate set a bit too slow. The flicker was not at all noticeable in the central area of my vision, but it was annoying in my peripheral vision. I realized that the peripheral area does not appear focused, but movement stands out more readily, while movement in the central, focused area is dampened to improve clarity of view. Hours in a blind either hunting or bird watching had already confirmed a consistent involuntary trait, at least of mine: any movement outside of my central vision caused my focus to immediately move to that spot. It all clicked. The human eye sees only a small area of the field of vision in sharp focus. Our evolution and heredity as predators, with our binocular vision, politically correct or not, causes us to see that upon which we focus and to exclude (if it doesnt move) that which is not. Although the angle of coverage of the lens on our eyes may indeed approximate that of a normal lens, what the brain records in memory approximates the coverage of a portrait lens. Perhaps if what you want to record is what you see at first glance, the 150 for 645 or 180 for 6x7 is ideal. If what you want to record is what your photo eye can select from a scene (that the rest of the world), it may be better to get away from 150/180far away. Does this explain why normal and wide angle lenses are such useful tools in the hands of the talentedthose who dont want to bring home what the next door neighbor saw when he was there? I havent seen this mentioned anywhere since that article came out, and the speculation in the preceding paragraph came to mind only after I wrote what precedes it. Are the author of that article and I the only ones who think the explanation for normal is misleading? Is the real explanation that, regardless of focal length, it is the angle of coverage that can be manufactured smallest and fastest? And, to depart from physics to metaphysics, any comments on my speculation as to how it relates to what we see as photographers?