[Leica] All cats are grey at f8

[lrzeitlin at gmail.com (Lawrence Zeitlin)]

Frank writes:
"If you are shooting at f5.6 Leica lenses are a bit of a waste of  
money. My Leica 50mm f1.4 is noticeable better that my Nikon 50mm f1.4  
-at- f1.4, but at f5.6 i see very little difference. The price  
differential is almost 10:1.
That is my experience in general, sure all lenses get better stopped  
down, very particularly the cheap ones. What makes Leica worth the  
money (if you have it) is it loses so little quality as you open up,  
compared to others.
IME."


I echo Franks opinion. A number of years ago one of the big US photo  
magazines did a survey of all major manufacturer 50mm lenses on the  
market. I forgot whether it was Modern Photography or Popular  
Photography. The survey included resolution, flare, fall off,  
distortion and all the usual suspects. While there were distinct  
differences wide open, not always in Leica's favor, when closed down  
to f8, all lenses were virtually identical. This finding was more or  
less confirmed by Canon in their detailed lens guide of 1969. In fact  
Canon said that when it came to photographic quality, lenses designed  
for lesser maximum apertures were better at reduced lens stops than  
faster lenses. Generally a f3.5 lens stopped down to f8 would  
outperform a f2 lens stopped down to the same aperture. The slower  
lenses had fewer elements and were of simpler design. Given the  
technology of that period this implied lower flare and internal  
reflection. Erwin Puts concludes that the f3.5 50mm Elmar lasted so  
long in the quality lens arsenal because the design was so simple that  
technical improvements in lens construction, including coating and  
rare earth glasses, made little difference in actual performance. I  
don't know if advances in lens design have closed the gap but if you  
commonly shoot at apertures of f5.6 through f16, then $3000 objectives  
are overkill. Better to use the money on a two year supply of single  
malt scotch or a lifetime supply of Belgian ale (or 100 Tilly hats).
Larry Z