Recently my wife Abby and I were working on a multi-stage garage clean-out project. One result of this is that she finds things that belonged to her father, whose life as a machinist led to him collecting thousands of tools and other items for his craft.
In our dusty unboxings during the past weeks, we came across a very cool little item I didn’t even know existed: a screw thread gauge. The device has dozens of little steel fins that are marked with widths in fractions of millimeters, and those fins are stacked together on a spindle so you can fan them out and measure the pitch of the threads in a screw.
Not only did I think this was a neat tool that I would probably never use, I also thought I should photograph it. I got out my two macro lenses, the AF Nikkor 60mm f/2.8, and the Tokina 100mm f/2.8. Both are wonderful lenses, and both could do the job. I chose the 60mm for no other reason than I hadn’t used it recently.
I set the thread gauge on the glass surface of my iPad, and cranked up three flash units plus the one of the camera hot shoe. I pointed one flash into a reflector to my left, one into a reflector over my right shoulder, and one in front of me to the right.
The result was pretty satisfying. Not only is the repeating pattern on the gauge intriguing, but the image ended up being dazzlingly sharp. It is so sharp, in fact, that despite my efforts to clean the gauge with compressed air before the shoot, you can see a fair amount of grime in the tiny spaces between the fins. It’s also sufficiently sharp that it created aliasing, the mixing of minute frequencies to create colors in areas of complex detail, right at the focal point.
It was fun doing this, and a nice departure from the kinds of things I shoot every day in my work.