[Leica] Bad bokeh

[Robert Monaghan <rmonagha@post.cis.smu.edu>]

see http://people.smu.edu/rmonagha/mf/bokeh.html for a good example of 
bad bokeh ;-) a few bad examples are more telling than good ones IMHO ;-)

the number of blades vs. bokeh argument falls apart since most lenses 
have their maximum degree of bokeh effect wide open (max lens aberration 
impacts basically) when the blades are retracted and not in effect on 
many optics. 

I haven't seen any discussion on variation of bokeh within batches of 
lenses; that would be interesting. For the few lenses I have in multiple 
identical examples, the bokeh effects seem to be similar in type and 
magnitude. 

I believe that the newer lenses are better corrected, which means that 
the older lenses with more aberrations have more interesting bokeh signatures

I think it would be useful to get more info and example photos of the 
bokeh factors of various lenses at different apertures so that folks 
could have a feel for which have nicer bokeh. It is hard to evaluate 
exactly what "good" or "creamy smooth" means in this context between 
observers, hence the need for photo examples. 

Finally, because these differences can be a major part of the impact of 
our photos, I think it is more useful and interesting than modest 
differences in corner performance which are rather subtle and missed by 
many clients and photographers in typical shooting scenes. It is also 
quite interesting as many of the better bokeh lenses are also bargains
(e.g., some of the russian copies in LTM and on M adapters). It is doubly 
nice to get a lens with a nice look at an even nicer price ;-) regards!

* Robert Monaghan POB752182 Southern Methodist University, Dallas Tx 75275  *
* Third Party 35mm Lenses: http://people.smu.edu/rmonagha/third/index.html  *
* Medium Format Cameras: http://people.smu.edu/rmonagha/mf/index.html       *


- --
To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html