jeff miller wrote:
Roger N. Clark (change username to rnclark) wrote:

jeff miller wrote:

This thread is providing some very useful information about SNR of
media and human eyes... keep it coming!



See:
Notes on the Resolution of the Human Eye
How many megapixels equivalent does the eye have?
The Sensitivity of the Human Eye (ISO Equivalent)
The Dynamic Range of the Eye
The Focal Length of the Eye:
http://www.clarkvision.com/imagedeta...esolution.html

Contrast thresholds data:
http://www.clarkvision.com/visastro/omva1/index.html

Roger


Great resource. Based on that data, I'd conclude that images captured
from my microscope might benefit for 65K x 65K resolution, so I'll use
16 bit D/A's to drive my scanning coils. Of course that kind or
resolution can only be rendered in print. And represents an 8GB file
size. And will take 2 hours to collect.... but might as well build it in.

The figure of 10,000:1 dynamic range in any "one view" corresponds to
about 12 bits. That's pretty much exactly the nominal dynamic range I've
heard quoted for the front end of an SEM.

But it might seems no current reproduction technology acheives quite that.

-Jeff



Ooops, 10K:1 is more like 13.5 bits.

But I'm finding a wide range of figures online for dynamic range of the
human eye.

I visited Barco's website in hopes of finding contrast figures for CRTs
and in a white paper comparing CRT and LCD displays, I think they tossed
out a figure of 100:1 for the human eye. 1,000 to one has been mentioned
here as well. The site referenced above so far holds the title for
claiming the widest range.

The white paper also tossed out a contrast figure for CRT's of 3,000 to
one, about 11.5 bits.

The human eye figure of 100:1 is the most surprising. The low contrast
of film is also surprising. I guess it (re film) shouldn't be, I know
that MgO is the most reflective substance as far as diffuse reflectors
go. I forget the figure.

-Jeff