Rediscover - Understanding Lens Contrast

Understanding Lens Contrast
And the Basics of MTF
By Mike Johnston Originally Published,  March 12, 2012
Many photographers — even some experienced and knowledgeable ones — seem permanently confused about contrast, especially when the word is used to describe lenses. In photography, like the word "speed" (which can refer to the maximum aperture of a lens, the size of the gap in a constant-rate shutter, or the sensitivity of an emulsion), the word "contrast" actually refers to several different things. "Contrast" in photo paper, for instance, or in a finished image, refers to overall (sometimes called "global") contrast, meaning how the materials distribute tonal gradation from black to white or lightest to darkest when we talk about lens contrast, weşre not talking about that quality. What weşre talking about is the ability of the lens to differentiate between smaller and smaller details of more and more nearly similar tonal value. This is also referred to as "micro contrast." The bett...