Originally Posted by
clemmb
I checked the ISO charts for 28, 35 & 50mm. The 24-105mm looks sharper to me.
You did not perform the comparison correctly. Read the [url="http://the-digital-picture.com/Help/ISO-12233.aspx]Chart Help Page[/url] where it says this:
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Lenses should be critically compared to each other only with test samples from the same camera body..
(Emphasis mine.) This is really important, because the 24-105 would look
much worse if the chart had a 50D body. For example, look at the 28-135. On that lens, both bodies are available in the test:
[url="http://the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?FLI=0&API=0&Lens=116&FLICom p=0&APIComp=0&LensComp=116&CameraComp= 474&SampleComp=0&Camera=453]28-135 on 1Ds3 @ 28mm f/3.5 vs 28-135 on 50D @ 28mm f/3.4[/url]
See how much worse the 50D looks? If the chart for 50D+24-105 was available, you'd see that it is worse than 50D+17-55.
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