I am considering buying a flash for my EOS 3. I am thinking about getting the speedlight 420ex or 550ex although i'm not limited to these two. I dont have any specific requirements as my photography is fairly general, although i take alot of black and white pictures. I would appreciate any advice, especially on what to avoid. cheers alex

-- Alex (a.douglas@qmw.ac.uk), November 22, 2001

Answers

Of the two oyu list, the differences are guide #s are 138 and 180 respectively. The 550EX can be manually zoomed while the 420EX can not. The 550EX is equipped with a diffuser designed to spread the flash to cover 17mm focal length (otherwise they both cover 24-105). The 550EX can be used as a 'master' in a wireless set up - this is why I like it the best, and why I would probably choose it over any other options (brands) if I knew anything about them. The 550EX is perfect for the EOS 3, and the 420 is a more affordable slave if you build a wireless system later.

-- Derrick Morin (dmorin@oasisol.com), November 22, 2001.

The 550EX also has a variable power manual mode and a multiple strobing mode if you think you might use these features. It also has several custom functions, one that even disables E-TTL in favor of straight TTL, so you don't have to deal with a pre-flash. These features are very usefull if you have a use for them, but are just more clutter if you don't. For my use the 420EX wouldn't cut it so I got a 550EX.

Another option to look at is the Sigma EF500 Super. It does everything (except the custom functions) that the 550EX does (and more) and has nearly the same power (less than 0.2 stops difference). It also works as a master in a Canon wireless system just like the 550EX does. The Canon is easier to operate and is built better but the Sigma is half the price. It's even less than the 420EX.

I'll sell you my 550EX. I want to buy two more Sigmas. :~))

-- Jim Strutz (j.strutz@gci.net), November 23, 2001.

Thanks Ralf/Jim, much appreciate the advice. At the moment i'm pretty skint so i might go for the 420 then in the not too distant future (i hope!) get myself a 550 (does that logic work!!). I had considered the sigma but was reluctant to go for a 3rd party brand. On reflection i'm not quite sure the reason for this, perhaps just a mixture of brand snobbery and inexperience as the sigma is pretty well specified. Maybe i'll go back to the shop one last time to have a look..... thanks again, great forum alex

-- alex (a.douglas@qmw.ac.uk), November 23, 2001.