Bob Blakely wrote:
I have some difficulty understanding this. Glass (even a Coke bottle bottom) has no ability to produce any discrete divisions in intensity, nor does it have the ability to compress the luminescence scale. Film does. Paper does. Digital sensors can. Sucky digital processing can. Glass doesn't. Now, one may have excess flair that can mask fine gradations at the dark end and give a muddy look...
Glass indeed does have the ability to compress the luminance scale. If you're saying what I think you are. It's what filters do and filters are basically coloured glass. BUT all glass is coloured. Some of it just looks less coloured to us. It's the differing qualities of glass in lenses, besides their optical formulation, that gives them their characteristics.
A perfect reproduction imposes no transitions from light to darkness, any discernable transition would come from the nature of the subject and it's lighting alone.
Not correct. I suspect you mean stepped transitions. Even then, not correct.
If you see high contrast, but the transition from light to dark appears too narrow such that the fine smooth transition from light to dark is not discernable, I'd say look to something other than the lens.
There are indeed other factors that may cause this but lens contruction is a perfectly possible one.
mike
