15 May 2008


The cat is out of the bag, the long awaited DA*200/2.8 has hit the market. The german test site Photozone was quick to test it, and delivered a report of mixed feelings. To sum it up, Photozone reports it to be sharp, with nice bokeh and nicely built.

But Adam didn't stay long in Paradise, did he? Photozone complains about Longitudinal Chromatic Aberrations (LoCA) and Purple Fringing (PF). These issues make me shudder. I once owned a Pentax SMC-K 500/4.5 which caused me some frustration in this respect. What makes me shudder, however, is all the trouble I caused the photographer who bought that lens from me. He has serious ambitions as a bird photographer and has had far more than a fair share of frustration over this lens. But any comparison to modern lenses is unfair. The K 500/4.5 is ancient. The way modern lenses manage such distortions is a good sign of progress in lens design. Testers like Photozone paying attention to it is also a good sign. These parameters were not considered in the tests of comparable Nikon and Canon lenses. I wish they were, for the sake of Photozone's credibility and brand-neutrality.

So what's the fuss?

The DA*200/2.8 will render bare twigs, air-strung power lines, flagpoles and other narrow picture elements in a purple colour instead of dark, almost black gray when shot against a bright background. The problem is most pronounced at f/2.8, and diminish quickly when stopping down. It's all gone at f/5.6.

So, one pertinent question remains. Who, in their right minds, run around shooting backlit twigs at f/2.8?

I know I don't.


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