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Lab Tests

Please note that MTF50 results for APS-C and Full-Frame cameras are not cross-comparable despite the same normalized [0:1] range used to report results for both types of cameras.


Resolution: Canon APS-C

The lens showed very good performance on an APS-C sensor camera. Image center as well as border resolution remained top notch throughout the tested aperture range. There practically was no weaknesses and with the resolution figures recorded in the MTF50 tests, the lens seems to out-resolve the 10MP sensor throughout the most of the aperture settings. The quality peaks in the f/4-f/8 range, where the lens can deliver outstanding 24in prints - and while the table below cuts off at 24in, you can easily see that the capabilities of the lens are quite impressive. Conclusion? Impressive performance, which would be hard to exceed.



Resolution: Canon FF

Contax Carl Zeiss Planar T* 100mm f/2 continued to showcase excellent performance even on a FF camera. Both center as well as border image resolution on 5D remained quite consistent throughout the aperture range, with no major variance across the frame. According to the charts, center image performance is slightly better then border, but visually, I highly doubt this difference would be noticeable. Conclusion? The lens clearly can handle 12MP sensor without any hiccups.


Chromatic Aberration: Canon APS-C

CA on an APS-C camera was somewhat of a mixed bag - aberration in the image center was minimal throughout the aperture range, but the levels were much higher around borders, with CA reaching ~1px at f/2 and then slowly sliding towards ~0.6px by f/11.

Chromatic Aberration: Canon FF

The lens did not show any significant improvement in chromatic aberration handling on a FF camera - center CA was minimal again throughout the tested aperture range, while border CA peaked at f/2 at ~1px and then slowly got to lower levels with stopped down apertures.



Carl Zeiss Planar T* 100mm f/2 showed pretty much non-existent amount of distortion. At +0.08% pincushion distortion would not be visible in real life hot.



Vignetting was fairly pronounced on a full frame camera, with color falloff exceeding 1EV at f/2, slowly dropping to a less noticeable ~0.5EV by f/4. On an APS-C camera, vignetting was much less of a problem. Even at its widest aperture, the lens produced only ~0.55EV falloff, and much less with stopped down apertures.


Chart Crops: Canon APS-C

Here are 100% crops, taken with an APS-C type Canon Digital Rebel XTi, comparing image borders at f/2 and f/8

Chart Crops: Canon FF

Here are 100% crops, taken with FF type Canon 5D, comparing image borders at f/2 and f/8