MTF50 Discrepancy? 70-200 2.8 IS

[piiooo]

Individual samples of lenses seem to vary. For example, compare Bryan's two samples of the 70-200 f/2.8 IS II. At 200mm f/2.8, I think they look pretty different in the corners. I would not be at all surprised if they are at least 200 points apart.

According to this article, MTF paragraph, other variablesthan production samples would belens aperture and object distance. Interesting stuff.

[Jon Ruyle]

Interesting article and point taken. But Bryan's two copies of the 70-200 f/2.8 IS II were compared at the same distance and same aperture.


As for dpreview and photozone, I agree the two 70-200's may have been compared at different distances and this may account for some of the difference (I personally have no idea how much, though).


Plus, nothing against dpreview or photozone in particular, but not everyone is as careful as Bryan. In general, tester error is probably a factor more often than it should be.

[piiooo]

Agreed on all 3 paragraphs, Jon. [Y]