“Why can’t I just point my camera at what I’m seeing and record that?” If you are looking for the answer you can find it here at Cambridgeincolor.com. It’s really one of the best articles I have read recently. There are a couple of very interesting facts:
1) Angle of view
“Although the human eye has a focal length of approximately 22 mm, this is misleading because (i) the back of our eyes are curved, (ii) the periphery of our visual field contains progressively less detail than the center, and (iii) the scene we perceive is the combined result of both eyes.” and “Our central angle of view — around 40-60° — is what most impacts our perception. Subjectively, this would correspond with the angle over which you could recall objects without moving your eyes. Incidentally, this is close to a 50 mm “normal” focal length lens on a full frame camera“
2) Resolution and detail
I guess most of us thought our eye would have more “Megapixels” than a camera. Surprisingly the answer is NO! Cambridgeincolor says: “A single glance by our eyes is therefore only capable of perceiving detail comparable to a 5-15 megapixel camera (depending on one’s eyesight). However, our mind doesn’t actually remember images pixel by pixel; it instead records memorable textures, color and contrast on an image by image basis.”
3) Sensivity and Dynamic Range
“Dynamic range* is one area where the eye is often seen as having a huge advantage. If we were to consider situations where our pupil opens and closes for different brightness regions, then yes, our eyes far surpass the capabilities of a single camera image (and can have a range exceeding 24 f-stops). However, in such situations our eye is dynamically adjusting like a video camera, so this arguably isn’t a fair comparison.“
Conclusion: “Overall, most of the advantages of our visual system stem from the fact that our mind is able to intelligently interpret the information from our eyes, whereas with a camera, all we have is the raw image. Even so, current digital cameras fare surprisingly well, and surpass our own eyes for several visual capabilities. The real winner is the photographer who is able to intelligently assemble multiple camera images — thereby surpassing even our own mental image.“
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And there is another interesting article at Quesabesde (Click here to read the google english translation) The question is: “Do digital sensors lose effectiveness after some time?” The answer is No!….But not a 100% No :)