Optically, I found the ZE & ZF to be the sharpest wide open with slightly cooler colors. The MM was nearly identical to the ZF, maybe a tiny bit softer (say 5% softer?) wide open - but it was such a small difference that I would not worry about it. The AE versions was the softest of the group and its coloring was warmer, not as bold as the ZE / ZF. There is about a 30 year ago difference between the AE and ZF, so the difference in coloring could be attributed to updated lens coatings, new glass formulations and / or degradation. At F5.6 all three lenses were indistinguishable when comparing sharpness and contrast.

The Contax AE version had the lightest focus ring by far, but that could have been unique exception. The Contax MM’s generally have a stiff focus ring (in my opinion). When the Zeiss ZF’s were first released, they too were notorious for stiff focusing. I found the ZE to be quite pleasant and easier to turn than the Contax MM’s.

One upside to the new Zeiss ZE is its macro abilities, but it is a larger, heavier lens than its 100mm Planar predecessors. With the Zeiss ZE stop-down metering is a thing of the past. And there are no adapter woes either. For me these are big selling points of the Zeiss ZE version; however, I believe then Contax version has a more unique 3D rendering. I have shot 1000’s of pictures with the Contax’s, so maybe with time I will feel different about the Zeiss 100mm ZE.

LENS PERFORMANCE

Some key stand out areas are the Planar’s micro-contrast, its depth of field (DOF) and overall flexibility. The 100mm Planar’s micro-contrast results in better gradients and more detailed textures. Compared to Canon L lenses such as the EF 135mm L F2 and EF 85mm L F1.2, the 100mm Planar produces subtler gradients and shows more detail. Where the Canon lenses tend to rush to deep blacks, the 100mm Planar holds more mid-tones and captures more detail in the shadows. In general the Planar has a gentler roll-off. The renderings have more nuance, more tonality in the mid-tones.

Another key difference between the 100mm Planar and its Canon counterparts is DOF. The 100mm Planar has proven to have a thinner DOF than the Canon 135mm L F2 when shot at equal apertures. Test shots were taken at the same distance and at the same aperture. According to the DOF tables the 100mm Planar should have more DOF; however, it proved to have 1 to 2 stops less DOF than the Canon 135L.

DOF is not a standardized metric. A Leica 100mm F2.8 Elmarit-R Macro APO, a Contax 100mm F2 Planar and a Canon EF 100mm F2 will all have a different DOF at F4. The resulting DOF is a function of the lens’ design. On-line DOF calculators ESTIMATE the DOF for given focal length, aperture and distance. This can be misleading because it implies that all 100mm lenses will perform in the same manner, and that is simply not true. There are also dramatic differences in how various lenses enter into the plane of focus and exit out of the plane of focus. The 100mm Planar’s transition is abrupt, easily separating the subject from the background.

The 100mm Planar’s shallow DOF makes for wonderful outdoor portraits - even at F5.6 there is terrific separation between the subject and the background. The 100mm Planar shots often have a very 3D feel to them. In contrast I do not like the 100mm for product shots because it lacks the needed DOF. Sharpness and resolution peak around F5.6 and seldom does F5.6 have enough DOF for a product shot.

The 100mm Planar performs equally well whether shooting close-up portraits or landscapes at infinity. The micro contrast plays its role which results in deep, rich textures. The added texture in leaves and foliage have the illusion of extra resolution. Overall the Contax 100mm Planar and Canon 135mm L F2.0 have similar resolution, but Zeiss’ superior contrast out-classes the 135L and gives the Planar images more snap. The Zeiss images “pop” and respond very well to post processing in Photoshop.

Other highlights for the Contax 100mm Planar include - essentially zero distortion and a very flat field of focus. Pictures are sharp corner to corner even at F2.0. The 100mm Planar is well known for its smooth bokeh (background blur) with rich, deep saturated colors. In the plane of focus the Planar is nearly free of any CA (color fringing). When shooting wide open there may be some slight CA with a light subject against a dark background or visa-versa. Compared to my experiences with the Canon 85L Mark I and Mark II, the 100mm’s CA is much less. Lastly, the 100mm exhibits subtle light fall off in the corners on full-frame when shooting wide open. In my opinion the fall-off combines beautifully with Planar’s F2 DOF rendering.