Ken Durling wrote:
> OK, thanks, Green. As always, a lot to learn. Now I have to figure
> out how they address contrast, AND bokeh.
In simple terms, MTF tests measure the ability of a lens to differentiate line
pairs, or, looked a different way, to resolve black lines against a white
backgound. So in essence an MTF measurement *is* a measurement of contrast (the
lens's ability to resolve the contrast between black lines on a white
background, or alternating black and white lines, however you care to think of
it). What it does not measure are things like chromatic aberations and
distortion, which is why MTF graphs are a useful but limited tool. (And of
course they don't take into account sample-to-sample variations.) Although
sharpness and contrast are not the same thing, they are related, and good
contrast resolution is important for making an image appear sharp. For an
interesting discussion of resolution, sharpness, and MTF, see the appropriate
articles at photodo.com (don't just look at the scores!).
This link might get you there:
http://www.photodo.com/art/Reso8.shtml
fcc
*
****
*******
***********************************************************
* For list instructions, including unsubscribe, see:
* http://www.a1.nl/phomepag/markerink/eos_list.htm
***********************************************************
