Lenses and Optics
Sigma has been releasing one great lens after another for a while now. Some, like the 35mm f/1.4 and 18-35mm f/1.8 zoom, have created feeding frenzies soon after (or even before) their release. Others, like the 24-105 f/4 OS, haven’t created a whole lot of fuss. So I thought we would do a little optical […]
Lenses and Optics
OK, I’ve done a couple of posts about critical focus for testing, and setting up an optical testing station. This post will provide some demonstrations about actually using it. I’m going to use lenses that we optically adjusted back into proper alignment as examples. I’m doing this because it’s a great opportunity to show you […]
Lenses and Optics
There are a lot of right ways to do optical testing. The gold standard is to put the lens on a $150,000 optical bench or run it through a well-equipped Imatest lab. But unless you have an optical bench or Imatest lab handy, that’s not practical. We have to optically test around 400 lenses a […]
How To's
By far the most common email and PM I get basically says, “I think my lens is optically out of sorts. What do you think?” The second most common is, “So what’s the best way to optically test my lens without a ton of equipment.” Years ago I wrote an overly long post about testing […]
Teardowns and Disassembly
The usual warnings apply: Do not try this at home. This post was made by semi-trained, semi-professional repair technicians who sort of know what they’re doing. The following blog post contains graphic images of the inside of a very nice camera. If such things make you squeamish, don’t read further. No cameras were harmed in […]
