symbolic codes - choice of clothes or colours - symbolism
audio codes - music and dialogue
Skateboard documentaries use a very different approach compared to something like wildlife documentaries, its a much more 'down to earth' and laid back style, with shots that should have been bloopers being added into the final product just to give the documentary character. Camera shots; this is also something that is very unique to extreme sports documentaires because they have to film things in a whole different style, for skateboarding the camera man while mostly been skating beind the talent crouched down to get the best angle possible(see picture 1).
For choice of clothing 99% of the time it is up to the talent what they want to wear, however if it is a film for a certain brand, 'Etnies' for example, the talent would have to wear their brand of clothing for promotional reasons. For the odd time they do not get to choose their own clothes would be in a film like 'Lords of Dogtown' because it is set in the 70s, so obviously they have to wear the styles of that age.
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Picture 1