Pentax smc da 55mm f 1 4 sdm vs pentax smc da 50mm f 1 8?

The 50mm f/1.8 is the one I'd start with. It's the cheapest fast portrait lens for Pentax APS-C bodies, and on APS-C it frames like about 75mm on full frame.

The 55mm f/1.4 frames a little tighter, like about 82mm, and its f/1.4 aperture gives more light and softer backgrounds. It's the better choice if you shoot in dim rooms or want more separation from the background. Both are autofocus primes for Pentax K mounts with no stabilisation, and both fit the APS-C bodies. Only the 55mm also works on the K-1 and K-1 Mark II, in APS-C crop mode.

If you're buying one lens for people, the portraits guide explains why the 50mm is the sensible first step.

Written by Claude from this site's pages.