[Leica] 180 report, part 2

[Erwin Puts <imxputs@knoware.nl>]

Both the 2 and the 2.8 focus past the infinity mark. The additional 
distance is more than 5 millimeters. The amount of glass and metal in 
these lenses is such that thermal expansion becomes an issue. The 
free space beyond the infinity mark has thoughtfully be provided so 
that whatever the temperature the true  infinity focus can be used.
On test.
The Elmarit 2.8/180 at full aperture gives an exceptionally high 
contrast over the whole image field, and exceedingly fine detail is 
defined with crystal clarity and excellent edge contrast. This 
performance extends over an image height of about 10mm, (that is an 
image circle of 20mm). The outer zones reproduce the details with a 
slightly lower contrast and a bit more fuzzyness at the edges. The 
apochromatic correction delivers true apo quality over the whole 
image field to the corners (no color fringes whatsoever). There is no 
decentring, no distortion and no vignetting. (you can measure a bit 
of light fall off, but is not discernable on the slides). Stopping 
down does not improve the image quality. The corners and outer zones 
become a shade crisper though. At f/8 the contrast drops a bit and 
thus the optimum is below f/8. But from f/2.8 to f/5.6 the 
performance is on the same level and so the full aperture is not only 
a very useful one, but also the optimum.
After f/8 to f/22 the contrast is a bit below optimum but overall 
image quality is above comment and so we have one of those rare 
lenses that can be used with utmost confidence from 2.8 till 22.
Close up perfomance ( about 2 meters) is absolutely equal to the 
infinity setting. There is some pincushion distortion, however. The 
overall imagery is even a fraction better than at infinity. This is a 
most remarkable behavior and can be explained by the mechanism of 
internal focusing. Only one lens element inside the lens moves when 
you focus and the designer has very skillfully used this shift to 
correct the close up performance. Not a real floating element, but 
sort-of, so to speak.
This lens delivers optical quality of a very high order indeed and is 
the best Leica lens I ever tested, better than the 2,8/100 (R) and 
the 2/90 (M). This lens alone would be a sound reason to buy into the 
R system.

The Summicron 2/180 at full aperture is almost on the same level as 
the Elmarit at 2.8. The overall contrast is exceptionally high and 
over an image height of 5 to 6 mm (image circle of 10 to 12mm) 
exceedingly fine detail is defined with excellent clarity and 
exceptionally high edge contrast. In the outer zones the contrast 
drops visibly, when one looks the definition of the very fine detail. 
Outlines of subjects are defined very very crisply. The far corners 
are quite soft and fine detail, while clearly visible is soft with 
fuzzy edges. Stopping down to 2.8 improves micro contrast in the 
outer zones and now the performance is almost identical to that of 
the 2.8/180. Further stopping down improves the micro contrast of the 
outer zones, but now the on axis performance drops a fraction. 
Vignetting is not detectable on slides, taken at full aperture. There 
is a very faint decentring. Apo quality is as expected. No fringes, 
hardly any  astigmatism etc.
Close up performance is identical to infinity performance and can be 
explained by the same mechanism as in the Elmarit 180.
The outstanding property of this lens at full aperture is its 
definition of the smallest possible detail with a very high micro 
contrast and overall contrast.  On location photography in twilight 
and semi-dark level of exposure (50 ISO at 1/4 to 4 seconds) shows an 
excellent power of penetration of distance: fine detail at a distance 
of 50 meter in very low contrast light is defined with outstanding 
edge contrast and subtle shades of colors are recorded with high 
fidelity. Colors itself are clean and transparent. Shots of models at 
about 5 to 10 meters in the twilight record details not visible with 
the naked eye. Portraits close up produce pictures with a very 
pleasing perspective and a recording level (even at full aperture) 
that would be a challenge for any medium format lens to equal.

To summarize this second part (the next one will look at flare, 
unsharpness gradient etc):
both lenses are the two best lenses I ever encountered within the 
Leica stable. The 2/180 is obviously a tripod only lens and performs 
superbly in its intended application: location and studio photography 
in a stationary situation. The catwalk is an obvious deployment as is 
model (glamour?) photography, where the low light capabilities of 
this lens extend the limits of twilight photography. Nature, and 
animal photography are also suitable areas. The 2.8/180 is a bit more 
versatile as it can be used handheld.
Both lenses have an extremely shallow depth of field (the Summicron 
at 2 to 3 meters operates at about 1 to 3 cm!). The accuracy of the 
R8 is fully capable to handle this and you can be assured that the 
plane you wish to focus on, is indeed recorded with the best image 
quality.
These lenses approach the ideal of a lens, that gives optimum 
performance at full aperture, do not degrade when stopping down and 
perform as well at close distance and at infinity  and give equal 
image quality over the whole image area (2.8) or a big portion of it 
(2.0).

As a closing off record remark: Dan C's prediction is not 
corroborated by this report, as  I can see it.


Erwin