If only John Belushi had lived long enough to do The Samurai Photographer.
Originally Posted by blansky
I won't pretend to know the answer - I was always told that 50 mm is a "normal" lens... but frankly (although its probably my favorite 35mm lens), I find that that is far from the truth.
Something that got me thinking: I just picked up a new set of eye-glasses today, and as usual, I keep seeing the frames and its giving me headaches! I know that this will go away, it always does after my brain adjusts... but, while cleaning the house today, quite by accident I found a long lost and presumed dead pair of sunglasses. They are Ray Ban Aviators, and I picked them up with some fondness (I got them when I was 17!), well, once the emotions subsided, I realized my glasses were still pissing me off. I took them off. I looked at them. I looked at the ray bans. I looked at my prescription glasses again. My spectacles are about a quarter of the area (lens) of the sunglasses! Wearing the Ray Bans felt like I just put on a facemask by comparison! And then I realized something:
Aviator sunglasses are known as such because they were designed for pilots to protect them from the sun. No thought was given to fashion, it was a case of form following function (and then it became fashionable, whatever..). A shape was concocted that covers the human field of vision as thoroughly as possible. My eye glasses were designed by a fashion designer, and hence are not worth the box they came in, optically speaking.
So, our eyes are in fact, a wide angle lens indeed. However, they feed the information to a brain, not onto a piece of "celluloid", a paper or a screen that can be taken in from a distance. Therefore, we make decisions about what we care about and what we do not care about. We often (mostly) look but do not "see" ( and I do not mean that in any philosophical way - just physically). So perhaps the perfect "normal" lens would be an ultra wide angle lens that would make all the performance testing types cringe (or sallivate atthe possible write ups). A lens that was really sharp in the middle, and not at all at the sides. A really, really cheap lens!
And one more thing: all things we see have one thing in common - they are in front of our eyes. Our field of vision is not - its in us so to speak, on our own little "film plane indicator" ( I would love to see someone with that little cirlce with a line through it tattooed on their head...). So, we extrapolate what we want to see from the information available, where as in a picture, we are inclined to take the whole thing in. Could we see more? Surely. Do we want to? NO, actually, it hurts our heads to try.
OK, well, I am sleepy. I need go beddy bye. I apologize for this rambling post - I doubt it proves anything... hope someone will get a lugh at it... since looking back now I believe I lost the plot there somewhere.
Hm, Ray-bans found after thirty years , your house cleaning sounds about the same as mine.
I think I deserve a degree in archeology every time I undertake this...
Originally Posted by Bentley Boyd
Me too. I've been cleaning house all week. Today, some of the junk leaves the house. Still a lot more junk to go, but I can only keep it up for a while.
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I agree to this...but sometimes (when at the beach in the summertime) I miss having the 400 mm eyes to enjoy the girls without having to appear like an old dirty bastard
Originally Posted by bjorke
You all, are confusing me.
I thought the the generally accepted lens is the one giving an angle of view of about 46 degrees, which is close to the human angle of view.
This will translate to a 46mm lens in 35mm format.
(At least this is more or less the most common textbook defintion I've been accustomed to.)
Too many Chiefs not enough Indians.....
How do you calculate it?
Originally Posted by Dimitri
As has been stated before in this thread, the human field of view is much wider than 50mm or even 35mm, in 35mm camera terms. Try looking at a fixed point and then moving your hand around from behind your head. Even keeping your eyes firmly planted straight ahead, at some point you'll become aware of your hand, and that point is much wider than 35mm. My guess is that it'd be somewhere between 16mm and 20mm, but that's only a guess.
This analysis, however, is incomplete. Part of the trouble is that the human eye has two different types of photoreceptors: Cones detect color but aren't very sensitive to dim light, while rods are more sensitive to dim light but can't distinguish colors. Cones are concentrated near the centers of our visual fields, while rods are spread out mostly in the periphery. Topping it all off, our ability to detect detail differs according to where in the visual field something falls -- it's better in the center than in the periphery, because we've got more photoreceptors in the center than in the periphery.
Putting this all together, if you wanted to simulate in a photograph what people see, you'd have to get a very wide lens (as above, 16mm to 20mm would be my guess), take a photo, and then use darkroom or digital techniques to wash the color from and blur the outer areas. Of course, we don't perceive the world this way, but that's a matter of our ability to attend to certain features (usually in the central areas) and our brains' ability to interpolate and create things that seem, consciously, to be quite different than they are, in terms of the raw inputs. (Did you know we've got visual blind spots where our optic nerves leave our eyeballs? You'd never know it in day-to-day visual tasks, but proving it is easy -- put two dots on a blank piece of paper, close your left eye, look straight at the left dot, and move the paper back and forth. At some point, the right dot will seem to vanish -- that's your blind spot. For me, with dots two inches apart, the blind spot appears when the paper is about 4-5 inches from my eye.)
In sum, there really is no lens that will truly reproduce the human visual field. Film (or digital sensors, for that matter) and the human retina are just too different for there to be a simple one-to-one correspondence.
I think that there are two issues here, 1) field of view and 2) perspective. A 40mm lens on a 35mm camera might aproximate the field of view but the size relationship between near and far objects will be out of proportion and unnatural because of the wide angle effect. A 135mm lens would offer a more familiar relationship between foreground and distant objects but would only cover a small slice of the scene as you see it naturally.
My theory is to come close to a true human perspective you would use a longer lens on a larger format camera to match both the prespective and field of vision. I have found that a 40mm on a 35mm is fairly comparable to a 150mm on my 4x5 camera. That might be an interesting place to start.
This is just my theory, feel free to contradict it.
That is called grain. It is supposed to be there.