Review Price £859.00
The new model has a lot in common with the HF S10. In particular, it's built around the same large 1/2.6in CMOS sensor with a gross 8.59-megapixels, 6.01-megapixels of which are used for video and 8.02-megapixels for still images. Canon doesn't add any interpolation, so the maximum still image resolution is 3,264 x 2,456 pixels. There are no changes to the recording formats available, either. The HF S21 records Full HD AVCHD at 25 frames/sec up to the top rate of 24Mbits/sec. An interlaced signal is used, but Canon's 25PF mode is available to encode true progressive frames within.
With so many excess pixels available for shooting video, Canon has put them to good use with its Digital Tele-Converter. This adds an extra 1.7x multiple to the relatively modest 10x optical zoom, for a much more impressive 17x total. Unlike a pure digital zoom, the Digital Tele-Converter doesn't involve a loss in resolution, although there are also 40x and 200x digital zoom options if you do feel you can tolerate this. But we wouldn't advise it.
Whilst the core specification is the same, there are key areas of improvement with the new model. The on-board memory has been doubled to 64GB, and there are now two SD Card slots instead of one, both of which support SDXC. So the maximum storage available would be 192GB, with both slots populated. Even at the top video data rate, that would be enough storage for 18 hours of footage.
The LCD has also grown from 2.7in to 3.5in, with 922,000 pixels of resolution, and acquired touchscreen capabilities. In tandem with Canon's Multiangle Vivid LCD technology, the display is clear and viewable even in quite bright conditions. And when it isn't, there's now an electronic viewfinder available as well, which extends from the rear sufficiently for comfortable usage.