Chapter 2
Leica R-Lenses
10
Vignetting amounts to 2 stops wide open, but can already be
neglected at 2.8, and is even lower than that of the Apo-Macro-
Elamrit at 2.8. The apochromatic correction is effective from
aperture 1:2 and can be seen from the non existant color frin-
ges at high contrast edges. Still the correction is not perfect. At
very steep black-white borders (and color-white or color/black
borders) a very small color fringe can be detected, but only
just and in high magnification. The unsharpness gradient is not
as smooth as can be seen with the Summilux 80mm. Some vei-
ling glare can be detected in strong back light and large areas
of sky that work as a light box. At distances below 1.5 meter
the definition of very fine structures softens a bit at the wider
apertures. Stopping down to 5.6 will save the day. Using the
Apo-Extender-R 2x, you get a very fine 4/180mm lens, that
should be stopped down to smaller apertures at distances
below 2.5 meter for best quality.
These remarks should not be interpreted as nitpicking. As
tester you simply stumble across some limits, how far off they
may be, and these should be noted. The Apo-Summicron-R
1:2/90mm ASPH is a superb lens in any sense of objectivity,
that beraks all previous limitations. With a weight of 520 grams
and a small size it may be sen as the ideal standard lens.
0
5
10
15
20
Y'[mm]
0
20
40
60
80
100
[%]
2.0
2.8
5.6
Vignetting
