Lenses and Optics
Measuring Lens Variance
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…
Sony FE 90mm f/2.8 G OSS Resolution Test
We got a pre-release set of Sony FE 90mm f/2.8 G OSS Macro lenses in for preliminary testing last week, and I was kind of excited about this lens for a couple of reasons. First it simply gives me a nice short telephoto prime option that has been lacking in the lineup (although the Zeiss 85mm Batis…
Just the Lenses: Sigma 24 f/1.4 Art Comparison
Most of you know I’ve been very impressed with Sigma’s new Art lenses. Their 35mm f/1.4 Art I still think is the sharpest 35mm prime lens made. The 50mm f/1.4 Art is also superb. When I heard about the Sigma 24mm f/1.4 Art lens, I had some mixed emotions. I was excited that we might get a 24mm lens…
A Quick Zoom Variation Demonstration
Sometimes I put up posts basically because I find myself answering the same email over-and-over. One of the emails I get a lot is: “I want the best copy of the xxxx zoom lens.” People get irritated because my response is usually something like this: Which focal length do you want the best copy at?…
Canon 11-24 f/4 L MTF Tests
I’ll be honest. I’m pretty excited about the Canon 11-24mm f/4 L lens. I love shooting ultra-wide and the chance to shoot this wide with a rectilinear lens on a full-frame camera has me pretty excited. But I’m also very aware of how near-impossibly difficult designing a lens this wide would be, so…
Just the Lenses: Tamron 15-30mm f/2.8
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…
The Nikon 300mm f/4E PF ED VR Test: Or Why I Don’t Test Just One Copy
As most of you know, we generally test multiple copies of a lens when we evaluate it, simply because we are so aware of copy-to-copy variation. But I got caught between a rock and a hard place this week. We received exactly one copy of the new Nikon 300mm f/4E PF ED VR lens and the purchasing…
A Brief 400mm Comparison
Canon shooters have a bit of 400mm excitement right now. The biggest news, of course, is the release of the 100-400mm f/4.5-5.6 IS II lens, replacing the original version that’s had a very long, successful run. Not quite so much excitement was generated by the release of the 400mm f/4 DO IS II…
Quick Zeiss 85mm Otus MTF Charts
Well, we finally got a few copies of Zeiss’ newest Big Ass Lens, the 85mm f/1.4 Otus in Friday afternoon. I didn’t have time to do a whole lot with them other than take a few shots, and run them through the optical bench for MTF testing, so this will be a short post. (Assuming I get a little more…
Just the Lenses: Canon and Nikon Mount 85mm f/1.4 (and 1.2) Primes
We’ll continue our Just the Lenses posts with the 85mm wide-aperture prime lenses. We’ll get through all of the wide aperture primes eventually, for those of you who like this series. If you haven’t read the previous posts, then you might want to go back and skim the introduction of the previous…
Field Curvature and Stopping Down
_Ignorance more frequently begets confidence than does knowledge._ Charles Darwin What I know that I don’t know doesn’t cause me much trouble. I don’t know the formulas for 7th order optical aberrations for example. I don’t know enough math to calculate those formulas even if I did memorize them.…
Just the Lenses: Canon and Nikon Mount 35mm f/1.4s
As I discussed in the last post, it’s impossible to accurately compare lenses from different mounts using any form of computerized target analysis testing (methods like DxO or Imatest). Target analysis tests an entire system (camera and lens). That’s a very practical thing, of course, but it has…