This is because the hard disk is 120GB, larger than any of the concurrent Everio models. There is an onboard digital image stabilizer, and optical zoom reaches 40x magnification. Other features include time-lapse recording mode, auto recording, face detection, and precise, responsive buttons for zoom and record. It includes media browsing software for Windows as well. It should be noted that this model's image sensor is smaller than even the lower-range new Everio models, and this is to keep the main emphasis on long recording sessions and lots of room for on-board storage. Models in lower price brackets may have more recording features and larger sensors, but lack the HDD capacity of the GZ-HD520.