Lenses and Optics
The Limits of Variation
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…
Notes on Lens and Camera Variation
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…
Lens Genealogy – Part 2
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…
Lens Genealogy Part 1
### 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…
The Apocalypse of Lens Dust
Apocalypse (from the Greek _apokálypsis_; “lifting of the veil” or “revelation”): 1. An event involving destruction or damage on an awesome or catastrophic scale. 2. A disclosure of something hidden from the majority of mankind. How appropriate the word apocalypse is for this little article. At…
Photo Lenses for Video: There is no Free Lunch.
SLR video cameras and the newer large sensor video camcorders, are often used with photography lenses — which provide outstanding optics at amazing cost savings compared to lenses specifically designed for film/video. A superb photography lens may cost $2,000; about 1/10 of what a good cinema lens…
Fun with Thumbtacks for Advanced Photogeeks
## Introduction There’s a scene in the old movie _Marathon Man_ where Dustin Hoffman wakes up strapped in a Dentist’s chair, mouth forced open, while the evil dentist drills into the nerves of his teeth, repeating the same question over-and-over: “Is it safe”? Tortured past endurance, he would…
The Development of Wide-Angle Lenses
# Introduction When I started my series about the history of lens development, I had planned three articles ending at the turn of the 20th Century. By that time many modern, excellent lenses had already been developed and it seemed a natural stopping point. After my series of 3 articles, I planned…
Who Invented the Telephoto Lens?
# Introduction When I wrote my series of articles on the history of lens development I largely covered the period around the turn of the century. By 1860, photographers had decent portrait lenses, and we discussed that most of the superb prime lenses in standard focal lengths we use today had…
Things You Should Know About Your Lenses, But May Not
This is not an article. A good article is like a five course meal, leading you through various tastes until you get to the big point of the whole thing: cheesecake. But I had a few things I wanted to talk about that weren’t an article in themselves, just blurbs, really. So I planned this one to be…
The Glass in Front of Your Glass: All About Filters
In the ancient days of film, any photographer worth his flash bulbs had a large set of filters in his bag. Filters to correct light, enhance contrast, add special effects to his images, you name it, there was a filter for it. Then came Photoshop and RAW and filters became quaint. Many of them,…
The Seven Deadly Aberrations
# This article is aimed toward the gearheads among us, those who want to know more about how things work. Reading it will not improve your photography even a microscopic amount. Then again, it might, actually, at least a bit. But for those who are interested in such things it’s a fun read. And for…