Videomaker – Learn video production and editing, camera reviews › Forums › Cameras and Camcorders › Professional Camcorders › Camcorder with changeable lens › Hi Dave – The 21x is the
Hi Dave – The 21x is the optical zoom number. 50x refers to the "intelligent auto" (iA) electronic zoom. Panasonic claims that iA zoom preserves image resolution, but these digital zooms usually cause some level of image degradation.
With or without the iA zoom, the image quality from the $998 GH3's 4/3" sensor and 72mpbs max bit rate will be much better than from the AG-AC8's tiny 1/4.5" sensor and 28mbps max bit rate.
Again, hope this is helpful,