Help required

Hi I am looking for some advice.
My hobby is motorcycles racing and I like to photograph it. For the last couple of years I have been using a 300D with a standard 70-300 lens.
I have just bought a new 30D and I will be soon buying a new lens. I have two in mind and would like some advice. One is a 70-200 F2.8 the other is an 80-400 F4.5 with Image stabilizer.
Which one would you advise? One thing to keep in mind is here in Ireland the weather can be dull a lot of the time.
Thanks.
www.bigjoephotos.eu

I'm not aware of an 80-400 IS lens for Canon. If what you have been using is less than bright enough for your needs, you need something faster like a f/2.8.

Sigma do the 80 - 400 lens

From what I have read the sigma's OS on that lens is pretty much obsolete - certainly well overdue for an upgrade. the Canon 100-400 rates much better, and will give pretty much the same focal range.

Whether or not a 70-200 gets you close enough only you can answer - is your 70-300 adequate in terms of focal length and are you always shooting at 300mm?

the main advantage to f/2.8 is that the AF will be faster, especially in servo AF

Just had another thought, that sigma's AF is reckoned to be slow so you will probably struggle with any motorsport.

steved110 wrote in post #2344117
...the main advantage to f/2.8 is that the AF will be faster...

And maybe more accurate. I'm not sure about the 30D but my 20D uses more AF points with a f/2.8 or faster lens.

If the f/4-f/5.6 70-300 doesn't let you stop the vehicles, IS won't help. IS will help with your unsteadiness only. Get the 70-200 f/2.8.

Thank's for the help. Looks like the 70-200 will be the one for me.
Joe.