Why would you use the APS-C Mode on a Sony Alpha Full-Frame Camera

In this movie tutorial I will show you the consequences of shooting in APS-C mode on a Sony full-frame camera and how to set up APS-C mode in the menus so that you can move between Full Frame and APS-C mode quickly. This movie also addresses a problem that some users experience when the 1.5 x magnification does not appear to work after switching APS-C mode to On.