Chip Louie WROTE: > > Excellent answer. I would add that better lenses including large UD > elements from the initial design stages can take better > advantage of the > high refractive index material to make more compact, lower > aberration lenses > than designs that simply replace and adjust an existing lens > formula for UD > elements. > > So now it comes down to those hidden support, design and manufacturing > features that don't show up in the spec sheets. ----------------------------------------------------------------------- Thanks. ALL lens designs are really based on an earlier design. Example, almost all f/2 and faster lenses for 35mm and 120 cameras are related to the Opic/Biotar which dates back about 100 years. Computer designing programs have helped make lens designs better and far faster. So even though you start fresh in many instances, you still base your work on earlier designs. Hard to tell these days with all the variations and Aspheric elements what the basis is, especially since it is hard to come by lens diagrams.
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