Canon 550 - 580 flash ?

[Shimmyhill]

I have a Canon 550 flash that i have been pleased with but have the opportunity to buy a 580 going cheap.

How much would i expect for the 550 as this could make the decision easy ?

But in real terms what is the difference between a 550 and 580, would be on a 30D ?

 

[iGiDK]

I jumped straight to a 580 so I don't know how the 550 compares in real terms, however this article might be useful to you:

http://www.the-digital-picture.com/Reviews/Canon-580EX-E-TTL-2-Speedlite-Flash-Review.aspx

my Canon Speedlite 580EX Flash gave me a slightly better result than the 550EX. But, more frequently the two gave me similar performance.