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LensRentals on two new Sigmas - so-so and oho!
#11
Also:

Quote:A chart stays the same - but lenses usually are corrected for ∞ . With a 50 × fl (50 × 14 mm = 700 mm) as a distance to the chart, one has to run into problems such as more vignetting and distortion at closer range.
No, we tested both. Distortion barely changes and has no influence on the results anyway, because we don't correct it. Vignetting is also not an issue in the analysis (unless it is really extreme, as it happens for example to be for many wide angles on the Leica M).

Also, loo at the focus scale on your lens: the test distance is much closer to infinity on that scale than MFD. So far I have not found any evidence that testing at this distance and the results I get from there contradicts the results I get with tested lenses "in the field".
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LensRentals on two new Sigmas - so-so and oho! - by mst - 11-26-2017, 10:07 AM

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