Max Guide No. 30 ft./9m at ISO 100
The Speedlite 90EX offers stronger flash performance than one might expect from its compact size. It has a maximum Guide No. 30 ft./9m at ISO 100, delivering ample power for everything from fill flash to serving as the main light source.
I ended up buying this flash after buying the EOS M. The "M" doesn't have a flash and there are many situations where you need one. The 90E was made for the "M" and really should have some with it. I bought it based on the size, but Canon sells other more powerful flashes for less money reducing the value of this flash. Functionally it does the job and plays nicely with other flashes.
January 21, 2013
Prices and specifications subject to change without notice. Actual prices are determined by individual dealers and may vary.