OK, here's the how it can go wrong (I'll post how they should look in another thread shortly).
1) ISO200, 2s @ f/5.6
The fireworks are overexposed, they give a nice amount of light to the surroundings but they're just a mush themselves. Pulling the exposure by 2 whole stops gives better definition on the firework so I should have either dropped the ISO or stopped down the aperture a bit more - the latter is easier to do usually.
2) ISO200, 1/2s @ f/10
The exposure is fine but there's just nothing really happening in the shot. The shutter speed is quite short so the light trails from the firework are quite short, although you can make out just how breezy it was by the motion blur of the smoke. This was an experimental shot due to the number of simultaneous fireworks being set off to try and reduce the number of bursts captured in the one shot. This one doesn't really work but with a bit more luck in the timing it could have been OK.
3) ISO100, 2s@f/9 (-0.9 stop exposure comp in RAW conversion)
After the tweak the exposure looks OK but this highlights two of the big problems I had with this particular display. I was too close for the lens I had (24-70mm on a 1DMkII) and there were too many simultaneous bursts to get a clean shot. The first is relatively easy to fix, either I should have taken a wider lens or moved back - something to be rectified next year. The second you're stuck with, once you get a decent position and a reasonable set of parameters going on the camera the rest is down to luck. Timing opening the shutter so that you get the whole of a burst takes a bit of getting used to so it can be a case of just shooting almost continuously for the whole display. The shots above come from a set of 325 taken in about 20 mins - with a 2s exposure you can see that the shutter wasn't closed for that long
