Human Eye equivilant?

[jcw122]

I dunno if it's just me, but I always see stuff w/ my own eyes, look through it through a 50mm'ed film SLR, and it just makes it way too narrowed. What is the size equivilant of one and 2 human eyes, like for lenses? Thx.

[timmciglobal]

You would need to offset 2 50 MM lens. There is no "field of view" combined with length equiv in lenses afaik because your brain overlays two images on top of each other to form your view.

As far as what gives the same total field of view, I'm sure there is some wide lens probably 12 mm or 10 mm that does close to it.

Tim

[paul_kelly]

I remember covering this in the Computer Vision module of my computer science degree. A digital camera equivalent of the human eye would be a pretty impressive beast - it would have to have around 500 megapixels!

More here: http://clarkvision.com/imagedetail/eye-resolution.html

[Rhys]

I reckon that 35mm in 35mm format is about the field of view of the human eye.

[Clyde]

I dunno if it's just me, but I always see stuff w/ my own eyes, look through it through a 50mm'ed film SLR, and it just makes it way too narrowed. What is the size equivilant of one and 2 human eyes, like for lenses? Thx.

While this isn't the answer to your question, I have performed this experiment:

Look through your viewfinder with both eyes open. Adjust your lenses focal length until the viewfinders view is as similar in size to your un-viewfinder-ed eye. That is to say, there is no apparent distortion in either eye. (I am still sure this could be put more clearly...) Take a snapshot, and check out the exif data. I found that it is roughly 49mm using a rebel XT with the kit 18-55 lens. BTW, while I don't have a zoom in the right range for my Pentax k1000, the view through a 50mm prime looks pretty near eye-like.

Non sequitorially, comparing the views between the two cameras reminded me of what a joy it was to use the k1000. I never used to think manual focus was at all inconvenient, and yet on those occasions when I need to use manual focus on my XT, I have the devil's own time with it.

It seems to me that viewfinder magnification or cropping could be the source of some inaccuracies, but I am not sure.

About the eye: The eye is incredible, and has a very wide field of vision (FOV). However, it is subject to substantial vignetting. There are many more rods and cones (color and light receptors) near the center of the FOV. There is also a blind spot where the optic nerve enters the eye. The size of the FOV and the degree of dropoff at the edge vary from person to person. Of course age generally results in loss of muscle tone, which lowers the resolving power of your lens. Lenses also vary in quality from individual to individual regardless of age. Eyes are not really designed for macro use, so excessive macro shooting (spending too much time reading these forums) can cause problems. Not only that, the equivalent of ISO is also subject to variation. Ted Williams once covered a bat with shoe polish, took batting practice, and was able to tell where on the ball he had made contact after every hit. Jeepers, creepers, where'd he get them peepers!?

Clyde