[Leica] 1,4/50 R and M

[Erwin Puts <imxputs@knoware.nl>]

At last the Summilux-R 1,4/50 report.

Summilux-R 1:1,4/50 (#3797918).
At full apertue this eight element lens
is of medium to high contrast and thus very visibly above the low to medium
contrast of the seven element predecessor. This is quite a performance
as conventional wisdom will tell you that more lens elements will
degrade contrast. Very fine detail is recorded with good clarity from
center to well into the outer zones. In the far corner area a slight
drop in performance can be noted. At f/2,0 the image outlines crispen,
as does the rendition of extremely fine detail and at f/2,8 overall
contrast improves again. Contrast of the extremely fine image details
now is of a high order. In comparison to the predecessor we may state
that the new one at f/2,0 is very much improved over the old one at
f/4.0. At f/4,0 the new lens  begins to record extremely fine detail
with clear and crisp edges over practically the whole image field, the
far corners excepted. From f/4,0 to f/8,0 this lens has its optimum.
From f/11.0 diffraction starts to lower the contrast of very small image
details. These small apertures are only needed when extended depth of
field is required. Closeup performance (±1,0 meter distance) is at all
apertures excellent. Curvature of field is much improved when compared
to its predecessor. We still can observe in the far corners a drop in contrast
at all apertures. Light fall off in the corners at full aperture is
hardly visible. Deliberate two stops underexposure failed to bring out
strong vignetting. Veiling flare at full aperture is negligable.
Suppression of light halos around small subject details is excellent and
carefull comparison shots with the Summilux-M 50mm showed the R version
to have a slight edge. Wide open performance  at infinity  has to be
balanced against close-up performance and here Leica have wisely choosen
to shift the balance away from the infinity plane. A 1,4 design will be
used at full aperture more often in the near distance range from 50
centimeters to let us say 5 meters.

The sharpness-unsharpness gradient is quite smooth and subject shapes
are very well preserved in the unsharpness zones. General conclusion.
The new Summilux-R 1:1,4/50 offers excellent image quality and Leica R
users can now shoot in available darkness and fully exploit the
capabilities of modern emulsions. To be quite clear: if you need to
record extremely fine detail to the last possible minutest image point,
the Summicron is to be preferred. For my formal comparison shots I use
Kodachrome 25 and 64, as these films still give the best sharpness (read
contrast) for very fine image details. Stopped down one or two stops the
new Summilux-R has that enviable balance of sharply rendered crisp
detail and smooth gradient of colour hues within small subject areas
that is Leica's current fingerprint. The image recording capabilities of
this lens far exceed the one offered by all current ISO400 films and are
on a par with the best of the ISO100 films. Kodachroem 64 would be an
excellent companion.

The outstanding capabilities of this lens are its high level of detail
recording from axis over the whole field and its ability to crisply
recording extremely fine details when stopping down. In this respect the
predecessor lacked some qualities.

In comparison to the Sumicron-R 2/50 the new Summilux is a better lens.
Optical aberrations( especially curvature of field and astigmatism) are
tightly controlled, and at f/4 to f5.6 the Summilux-New edges ahead of
the Summicron-R.

Compared to the Summilux-M the differences at full aperture are small,
but not inconsequential. On axis performance is more or less equal, but
the R wins in the field, significantly! At f/2,8 the M vesrion records
extremely fine details with commendable crispness, softening when going
to the corners.At f/5,6 we see a level of performance comparable to the
Summilux-R New. With one big exception. The M suffers a bit from loss of
contrast especially in the tangential direction. (Expanation in the
forthcoming VIewfinder article).

Summarising: the 1,4/50 Summilux-R defines the current state of the art
of large aperture standard lenses. It outclasses the 1.4/50 Summilux-R by a
mile. It edges ahead of the Summicon-R and improves upon the Summilux-M 1.4/50.
Non-scientific comparison pictures with the Summicron-M show comparable
performance in most picture taking situations. The Summicron-M is still the
lens to beat.
The Mandler era is not yet over. If you need the utmost of recording
capabilities the new
Summilux-R needs f/2 or smaller. Its wide open performance is outstanding.

Next in line is the 24 for M and R

Erwin