After receiving my 1Ds on 29 November, I briefly tested the 2 wide-angle lenses I owned, the Canon 28mm/1.8 and the 16-35/2.8, for chromatic aberation (CA). I was disappointed in the CA performance of the 28/1.8 and started looking for a replacement. I found that while there are not very many 28mm/1.8 Canon-AF lenses around, Sigma has 2. The earlier and less expensive is the Ď28mm f1.8 II Asphericalí. I found mine thru eBay for $130 delivered, from Sharper Photo. In testing, I found it never better than my Canon so I returned it. The Sigma Ď28mm f1.8 EX Aspherical DG Macroí is the later version and is quite a handful compared with its earlier brother or the Canon. It uses 77mm filters, fortunately a common Canon size. Yet itís quite affordable at only $204 from Delta. BTW, I use a prime 28 for panoramas, something thatís difficult to do with the 16-35, as its nodal point is about 3 inches (8 cm) forward of its mount.
I shot some Ďlandscapesí out my west-facing garage, into the bright Phoenix sky (but not into the sun). I included in the tests my 16-35 which is turning into a great lens on the 1Ds. I shot large fine JPGs (because I didnít feel like investing the time to convert these) and used MLU, selftimer, Velbon Carmagne 630 CF tripod, Kirk BH3, and a cable release.
I carefully compared center sharpness at f4, f8, and f16, and corner sharpness and CA at f8 and f16. Results were interesting. The 16-35 won overall, something that surprised me since itís a zoom. I guess those Canon lens designers are earning their pay lately! Of the 7 things scored, the Canon 28 was best in only one, corner sharpness at f8 (where it was worst in CA), while the 16-35 took 4 bests and the Sigma 3*.
Again, overall, the Canon 16-35 won, with a average score of 2.57 (of a possible 3), which probably is one reason it costs around $1400. Second was the Sigma with an average score of 2.29, while the Canon 28 was a distant third at 1.29. It was clearly the worst at CA, but the differences in sharpness among the three were much tougher to see.
Iíll be keeping the Sigma 28. Itís worthy of mounting on the 1Ds.
*ĖThat totals 8, not 7, because 2 tied for best in one criterion.