Canon EF 800mm f/5.6L IS USM Lens Review

The autofocusing system on the review lens was up to the challenges presented by its physical dimensions and weight. We found the focus limiter particularly useful when shooting subjects whose distances we could estimate. Autofocusing was almost silent and generally faster than we had expected, even when focus limitation was not engaged, which speaks volumes for the system's capabilities. Hunting was also relatively infrequent for such a fast, long focus lens.

The 5D's bright viewfinder image made focusing manually a viable option. Manual focusing was very smooth with this lens and the ring was very well damped, offering just enough resistance to make setting precise focus relatively easy.

The overall performance of the image stabilisation system was outstanding. Even though there were many blurred shots in our test sequences, when considering the constraints we placed upon the test lens it is surprising we
captured so many shots that could be classed as 'keepers'.

We were unable to run any Imatest tests on this lens because there was insufficient distance leeway in our testing set-up (which only extends to just over 200mm focal length lenses in 35mm format). Consequently, all assessments in this review are, of necessity, subjective.

Resolution in test shots appeared to be at least equal to that of similar shots taken with the EF 200mm f/2L IS USM lens. We found no evidence of coloured fringing (and none was anticipated) in test shots. However, some corner vignetting could be seen at f/5.6, although it was less noticeable at f/8 and no longer evident by f/11. In our opinion, it would never be noticeable enough to impair picture quality.

Colour reproduction was also very good and we found little evidence of flare and ghosting in shots of backlit subjects. The camera was also able to record its full dynamic range. Performance was equally good with both the camera bodies used in Photo Review's tests, which speaks volumes for the overall design and construction of this impressive optic.

Margaret Brown

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