RE: [Leica] RE: I've seen the BOKEH!!!

[Simon Pulman-Jones <spulmanjones@lbs.ac.uk>]

Dan Post wrote:

>>>>>>>>>I was wondering that the
relative size or diameter of the entry aperture of the lenses have any
effect on bokeh and the overall quality of the image?
The Noctilux has a very large front element, albeit to gather as much light
as possible, and to funnel it into  maw of that great lens.
Perhaps, the large opening, when translated to the interior, the out of
focus portions have a greater aberration due to the relatively large angle
that some of the light must traverse.<<<<<<<<<<<

Dan, this seems like a plausible theory - but, to be honest, though these 
things are absorbing and fun to think about, and some of the things that we 
hear about lens performance seem to make such nice sense - like the fact 
that symmetrical non-retrofocus designs like the Super Angulon have 
inherently fewer aberrations - simple is best - I feel that I am about as 
far from understanding photographic lens optical design and effects as the 
ancients were from understanding how the solar system works - or as far as 
we still are from really understanding how the mind works. People like 
Erwin are like the neuro-scientists of optics - they understand quite a lot 
about what is going on inside, but are only too aware of how desperately 
complex a mixture the sum is of the parts - and people like us that are 
interested in the way the lenses work are like the psychologists who 
attempt to understand what goes on in the brain by looking at what it can 
and can't do when it is damaged in particular ways - we make deductions 
from what we see the lenses doing in varying circumstances but we don't 
have a very good idea of why things work the way they do.

I suppose the fact that it's not an exact science gives all the more 
strength to the mystique, and makes experimenting with the differences 
between lenses so absorbing and addictive.

All the best,

Simon.