Category Archives: Lenses and Optics

Variation Measurements for Telephoto Lenses

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We're nearing the end of the Varation series for prime lenses. If you are joining in late, you may want to go back to the original article for an introduction into the methods used. Today will look at the short telephoto group, lenses ranging in focal length from 85mm to 150mm. We've also included a summary table of [...]

Variation Measurements for Wide-Angle Lenses

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When we started this series, we introduced our methods using 24mm lenses, then followed up with looks at the 50mm and 35mm groups. Today we're going to go back to the wide-angle lenses; the ones we expect to have the most variation of all. We probably should call this post the Zeiss Invitational, since they [...]

Variance Measurement for 35mm SLR Lenses

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Last week we posted optical bench MTF and copy-to-copy variation measurements for 50mm SLR lenses. We're going to continue that series this week with the same measurements for the 35mm lenses. This set should fill out the wide-to-standard range lenses and gives us a lot of interesting data as we continue to look at what factors [...]

Measuring Lens Variance

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Warning: This is a Geek Level 3 article. If you aren't into that kind of thing, go take some pictures. I've been writing and discussing the copy-to-copy variation that inevitably occurs in lenses since 2008. (1,2,3,4) Many people don't want to hear about it. Manufacturers don't want to acknowledge some of their lenses aren't quite as [...]

Just the Lenses: Tamron 15-30mm f/2.8

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Our Just the Lenses posts are optical tests where we compare various lenses on the optical bench. Unlike DxO or Imatest test results, no cameras are involved, eliminating one of the major variables. It's particularly useful when we're looking at third-party lenses that can be used on various cameras. It's hard to extrapolate the results of a [...]