Note that the video below is limited in its frame rate by the YouTube encoding - the original file is much smoother. You can still get an idea of the focussing going on though, plus the audio is pretty much as the original clip. Don't forget to click on the '360p' legend once you've started playback and then on '720p' and make the video full-screen.
From Damian's piece:
"...this updated application will look familiar to you, but it’s much faster to use and more intuitive. Moving the video/stills mode switch to the top left has provided an extra slot on the right which we’ve used to provide direct access to the scene modes from the viewfinder and in the case of video, exposure compensation is available in place of the flash control for direct accessibility.
But the enhancements you’ve been wanting most are 30fps video and continuous autofocus.
Smoother video
We’ve spent a lot of time optimising the code here to make the video smooth and frame-rate stable. This allowed us to increase the video frame rate to 30fps and achieve excellent stability. Using the older code resulted in less stable frame rates. Using the Beta Labs application you’ll get 30fps in auto mode. This provides significantly smoother videos, especially during panning. There’s been a lot of online discussion around whether 30fps is really needed, given movies are shot using 24fps. With movie cameras the time interval between each frame is extremely short compared to the time the shutter is open. Whereas with electronic shutter-equipped devices such as the N8, the interval between frames can easily be greater than the time the sensor is exposed. By increasing the frame rate with such devices, the interval between frames is reduced resulting in smoother video....
Continuous auto-focus in video mode
The Nokia N8 has the industry’s fastest focusing system for capturing stills. This is achieved by using a combination of a specially-developed focus-control algorithm and a piezo lens drive. But this speed comes at a slight cost [when capturing video and attempting auto-focus]. The downside is that piezo mechanisms can make more noise than the voice coil lens drive mechanisms used on other devices. To combat this issue, we’ve also developed a noise filtering system which specifically extracts the noise pattern the piezo lens drive emits from the audio signals. It works similarly to noise-cancelling headphones. This took quite some time to get just right, as we didn’t want to impact the already excellent audio recording capability of the N8, still one of very few devices which record audio with a stereo ambient audio track.
It is possible to use the continuous autofocus by selecting close-up mode at distances from 10cm through to infinity, but we’ve optimised it more for close-up. So at longer distances it may not work quite as expected. I’d personally recommend using the regular auto mode if you know your subject will be further away than 60-80cm and /or you’re shooting in very low light."
Go grab the update for yourself. You'll need Symbian Anna in place already and note that it's advisable to restart your N8 after applying the update.
In my tests so far the continuous auto-focus works well, but the noise-cancellation of the piezo lens motor noise does reduce audio quality markedly. Still, 'close-up' video is a useful function to have (e.g. for pets, nature, devices!) with normal 'Auto' mode best for general video and when there's speech to be captured.
[Updated] there's a patched version there now which handles 30fps capture correctly....
Steve Litchfield, 22 August 2011, All About Symbian