Canon 580 EXII

[arash_hazeghi]

I want to get a flash for my 40D, I have two questions.
1) what is the effective range for 580 EXII and how much does it really help for in flight and stationary shots (as a fill light say in backlit situation)
2)which beamer should I buy?

Thanks:)

[DennyKyser]

The range of the 580 ex II depends on how much light you need to hit the subject. Obviously if your trying to freeze action it will have to be pretty close, if your only needing to add a little fill, or brighten some shadows or eyes, will work much further. Not many on camera flashes any stronger than the 580.

Birds in flight, I can not say, but would think you would have to be quite close for it to have any effect.

What is nice about the 580 II is its hi speed sync, can sync at any shutter speed making it a very good fill flash in bright sun.

[Doug Brown]

It's a great flash, and the output is quite powerful. It can really help make images better. I don't tend to use it for flight because I usually hand hold. There is a matching Better Beamer for the 580; it's called the FX3.