[mole2k]

I find if the cars are comming towards you then the AF is most likely to not be able to keep up so your better picking a spot and taking the picture just before the car comes into focus (Gotta go just before otherwise the picture will be of the car as it's out of focus due to the delays in your body from thinking about pressing the shutter to actually pressing it and then the camera responding).

Shutter speed I try to keep between 100-250th to keep thinks blurred so it looks like the cars are more than just parked there although depending on the shot you can go for higher shutter speeds. TC's for example dont usually run spoked wheels so unless you go for a very low shutter speed to get noticable blur on the tarmac/scenery they always look parked. Off-road can use higher shutter speeds as you can then catch things like dirt flying and the car frozen in mid air .

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