Category » Technical Discussions

Lenses and Optics

Are Zooms Always Sharper at One Extreme or the Other?

By

There is a statement often repeated about zoom lenses, which I have assumed to be generally true, or at least historically true. “All zooms are sharper at one end than the other.” I also hear a lot of people saying they bought Zoom A because it’s sharper than Zoom B. Is that sharper everywhere? Just […]

Lenses and Optics

The Limits of Variation

By

A few people were more than a little amused that I, the ultimate pixel-peeper, wrote an article demonstrating that all lenses and all cameras vary a bit; that you can’t find the ultimately sharpest lens.  Each individual copy of a given lens is a little different from the other copies. A single copy will behave […]

Lenses and Optics

Notes on Lens and Camera Variation

By

A funny thing happened when I opened Lensrentals and started getting 6 or 10 copies of each lens: I found out they weren’t all the same. Not quite. And each of those copies behaved a bit different on different cameras. I wrote a couple of articles about this: This Lens is Soft and Other Myths […]

History of Photography

Lens Genealogy – Part 2

By

For those who missed all the excitement, in Part 1 of this series I discussed that almost all modern SLR lenses derive from one of 6 types of lenses that were basically in use by the 1920s. Part 1 covered the first three lenses: the Symmetrical, Double Gauss, and Petzval lenses. Those three lenses give […]

History of Photography

Lens Genealogy Part 1

By

In which I begin to answer the question “Why Do You Put the Lens Diagrams on Your Website?” Where do new lens designs come from? I knew that today’s lenses are all designed using computer programs, but  I was surprised to find new lenses aren’t designed from scratch. Designers start with an existing lens design […]

Follow on Feedly