Canon's FS11, punched above its weight in image quality terms, and with an identical sensor the FS21 wasn't going to be a sea change. However, it does perform slightly better in low light, with a brighter image overall. There is a lot of grain visible, though, which obscures fine detail. So whilst the FS21 does a better job than most camcorders with 1/6in sensors do in low light, JVC's latest models with a similar specification perform just that little bit better, with less grain visible.
In brighter conditions, the FS21 produces really quite commendable video for a standard definition model, as did its predecessor. Colours are bright and saturated, which you can tweak with the image effects if you prefer more or less vibrancy. The picture is sharp, with the autofocus and exposure reacting well to changing conditions. Overall, the FS21 fits the bill nicely for a budget point-and-shoot camcorder, picking up an attractive image except in the poorest illumination.
Video is recorded in MPEG-2 format to the now relatively ubiquitous MOD file type, which incorporates Dolby Digital audio. This is now widely supported by editing software, although some apps will prefer the files are renamed as MPG. If you just want to watch footage on a TV, the AV mini-jack provides composite video and stereo RCA audio via a breakout cable.
The Canon Legria FS21 has a lot going for it. Video performance is great for a camcorder this size and there are a few extra capabilities readily available when you want a little bit more control. However, its image quality is slightly behind JVC's Everio GZ-MS120 in low light. The JVC is lacking a few of the Canon's features and you will need to add your own memory as none is built in. But at over £100 less than the FS21, it's better value overall.