What is Diffraction?
One of the most concise, straight-to-the-point, and easy to understand definitions I found was at Cambridge in Colour: Diffraction is an optical effect which limits the total resolution of your photography. My understanding of diffraction was fairly basic until recently. I knew that if I stopped down too much, I would eventually start to lose resolution due to diffraction. One thing I didn’t know was that different resolutions can expose diffraction at different f-stops.
My camera setup for years has been a 24MP Sony A7 with the Laowa 60mm f/2.8 lens (when I’m shooting macros). I’ve kept an eye out for a second-hand A7R camera for a while and recently found a deal on a 42MP Sony A7RII. Using the same lens on that camera with the same settings I use on the A7 wasn’t producing the results I was hoping for.
As it turns out, diffraction can be a deep and complex rabbit hole. I went just a little beyond the surface-level stuff and learned about things like airy disks and diffraction limited aperture calculations. It was more complicated than I was willing to pursue – I don’t feel like learning about physics as a hobby (not right now). However, knowing just a bit more about it will help to guide my decisions on which camera body to use with which lens for which type of photo I am trying to take.
If you’re in to learning about physics and stuff in your free time, you can dig through some of the resources I found on the subject at the links below. Have fun!
