The already big selection of 50mm lenses will grow even more. Yongnuo is expected to announce the YN50mm f/1.8X DA DSM PRO lens quickly. According to the teaser on Fuji rumors, the lens ought to have a backlit show, similar to the Viltrox AF 16mm f/1.8 FE that I talked about earlier. Today’s quick tutorial is a throwback to the times before electronic cameras, with out autofocus, built-in meters, and other fashionable conveniences. The Sunny 16 technique for determining proper exposure was one of the best “rules” again then, and it could bail you out of a jam right now…