[Leica] 50mm Summicron and Summilux

[Thomas Kachadurian <kach@freeway.net>]

Luggers:

As I promised, I have done some side by side test of a current 50mm
Summilux-M and a classic rigid 50mm Summicron-M, Wetzlar. I'm no scientist,
still, my method was pretty sound. I cleaned both lenses, and both had no
filter. I used the build in hood for the 'lux and a 12585 hood on the
'cron. Both were mounted on the same M-4p, which was on a good tripod. I
logged every frame and shot a series of 4 to 6 frames with one lens, then 4
to 6 frames with the other lens, so comparison frames were on the same roll
of film. I used Velvia, which I souped myself, so all rolls were in the
same tank. I shot pictures of things with depth and detail, not targets. I
examined the film with an 8x Schneider and 4x Fuji loupes. For laughs I
also shot everything with a Canon EF 50mm 1.4 USM on an A2.

The most important thing I learned was that the shutter on my M-4p is
pretty variable at 1/500 and 1/1000, easily 1/3 of a stop off, and
sometimes as much as a 1/2 stop. The other major finding was that the
Summicron does not go to f1.4.

There is nearly no qualitative difference between the two lenses, but they
are different. The Summicron, particularly wide open, is a bit warmer,
something I like, but the Summilux might be considered more neutral. 

At F4 to F11 the lenses are identical in every way. If I had not carefully
marked the frames I would have had no way of telling them apart. Also, at
any F-stop, and any focus distance greater than 10 feet I could find no
differences at all.

Both lenses have lovely Leica boke, which is very similar, what I think of
as a watery softening of out of focus details rather than blurring. At
closer focusing distances, 4 to 6 feet, at f2.8 and f4.0 there seems to be
more detail in the out of focus areas rendered by the Summicron, edges are
better defined. At 2.0 there is no visible difference in the plane of
focus, but there is more contrast in the out of focus areas with the
Summicron. This may also be why at 2.8 and 4 the Summicron seems to hold
more detail in out of focus areas, but at 2.0 you can clearly see the
greater contrast. The Summilux is no slouch, and without the differences
from exact frame to exact frame, I would not have observed anything but
outstanding performance.

I tried to find something to shoot that would test edge sharpness wide
open, but short of a brick wall I couldn't find any real shooting situation
where it's an issue. The brick wall test shots looked identical with both
lenses. 

Both lenses handle flair very well, in my experience, as only Leica lenses
seem to be able to do. Flair control is surprisingly good with light
sources in the frame. There are artifacts of flare--a loss of
contrast--with light just out side the frame on the Summilux that isn't
there with the Summicron. I suspect it's because the pull-out hood is so
shallow. Oddly enough, it seemed worst at f4. 

Conclusion. You may be able to find a significant difference between these
two lenses shooting targets, but I had a hard time finding anything at all
to observe. The Canon lens was clearly a different breed, not bad, but much
different. I am splitting hairs to find differences at all between the two
Leica lenses.

The Summilux is only a bit larger, and if you stick to the black version,
only a bit heavier. Having used it extensively now for two weeks, I have
also found I only shoot at 1.4 rarely, but also when I least expect it. I
like having the extra stop, and the bulk is a small price to pay for it.

Anyone want to buy a 50mm Wetzlar Summicron?

Tom


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Thomas Kachadurian
WEB PAGE: http://members.aol.com/kachaduria