13 May 2011

Shooting video for online delivery

Use a tripod


The best advice I can give is to use a tripod whenever possible if you are shooting video footage intended for online delivery. The compressed movie will have a much smaller file size and therefore a lower datarate (faster download) than a similar movie which uses footage shot with a hand-held camera.

Why is this? Codecs (compression/decompression formats) compare adjacent frames in your movie and the less difference there is between frames the more effective will be the compression. Footage shot using a tripod will have objects which remain in the same place and retain their colour information (barring extreme changes in light conditions) and the background will remain pretty much the same across the frames. The codec will use occasional key frames to take care of these similarities and for the frames in between will only have to compress the differences – the objects that move or change. With footage shot from a hand-held camera practically every pixel of every single frame will be different due to camera movement and this will result in a higher datarate.

If you are using a tripod you might also consider moving the camera/tripod well away from the scene you are shooting and using optical zoom. Once you've established your point of view, zoom right in on the main object of the shot and manually focus on it. Then zoom out slightly to your desired frame composition and you should notice that objects behind and in front of your focus of attention are slightly blurred. If you like this effect then you have the added bonus of shooting footage which will compress even better.

Hand-held


Most movies are of course a combination of hand-held and tripod-mounted shots, and there are times when a hand-held video camera is the only option. You can reduce unwanted camera movement by zooming right out. Zooming in will only exaggerate camera movement so you should instead move towards the action you are shooting and leave the zoom out altogether. In a well lit scene practically everything should be in focus. My wife Genie followed this advice when shooting her first movie which you will find below.

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