Like the other two previous pictures, this one too has been taken by a Pentax K-5 housed into an Aquapack 458. This underwater housing, at least for APS-C dSLR, is a cheaper alternative to the more expensive, though bigger and better engineered, Ewa Marine. It fairly easy accommodates the camera and the DA* 16-50, but using this lens that has a 77mm filter thread forces the use a focal lenght of at least than 40-45 mm, otherwise the border of the external cap fills-in the picture. A DA* 16-50 at 16mm (I repeat: with a 77mm filter thread) is the bigger lens that can be accommodated into the housing, but…