I'd have to add that Michael's optical physicist is ... sort of right. That's the problem when dealing with physicists and engineers, you only get a technical opinion. I feel safe saying that since I do have a degree in physics.
Originally Posted by Michael Kadillak
So let's have the optical physicist tackle all the criteria for which the Dagor is desirable, and not just the optimum optical performance. Here's what I'd ask the optical engineer to design:
It has to have the the same, or better, circle of illumination to 5 lpm (coverage) as the Dagor
It has to have the same, or better, circle of sharp coverage as the Dagor
It can't weigh any more than the Dagor
It can't cost any more than the comparable plasmat that replaced it.
I'd be interested if such a lens is possible. And it might very well be possible. I've always maintained that if Schneider made the Super Symmar XL series at f:6.8 to f:11 in more focal lengths (like the Dagor), there wouldn't be any discussion at all about Dagors, they'd all be sold.