What is the pentax smc da 40mm f 2 8 xs good for?

The Pentax smc DA 40mm f/2.8 XS is an ultra-thin pancake prime for APS-C, so it's a sensible pick for a small, light carry-everywhere kit. On APS-C it frames like a 60mm lens on full frame, a comfortable standard-to-short-telephoto view for portraits, street, and everyday subjects. At f/2.8 it gives about the background blur of f/4.2 on full frame, so it's not a dramatic subject-isolator, but it's pleasant for separating people from their surroundings.

It fits a long list of Pentax K bodies, including the Pentax KP, the Pentax K-3 Mark III and the Pentax K-70. On the full-frame Pentax K-1 it works in APS-C crop mode at fewer megapixels.

If you want more background blur for portraits, the portraits guide explains why a faster lens or a longer focal length does the job better. For the reasoning behind the numbers, see the focal length converter.

Written by Claude from this site's pages.