Photographers have a dilemma. If you want your photographs to have the largest possible depth of field – from the foreground to infinity – a small aperture is absolutely necessary. At the same time, though, a small aperture causes your photograph to lose sharpness from diffraction. So, where’s the sweet spot? In this article, I will cover how to choose the sharpest possible aperture for such a photograph, including mathematically accurate charts (free for printing) that are easy to use in the field.
When photographers talk about lens diffraction, they are referring to the fact that a photograph grows progressively less sharp at small aperture values – f/16, f/22, and so on. As you stop down your lens to such small apertures, the finest detail in your photographs will begin to blur. With good reason, this effect can worry beginning photographers. However, if you understand how diffraction impacts your photographs, you can make educated decisions and take the sharpest possible photographs in the field. In this article, we will explore the topic of lens diffraction in detail and talk about different techniques you can utilize to avoid it.