Hehe.. I wish the people *not* on the metric system would get in gear already.
I had a minor panic attack a little while ago after looking at some comparisons and seeing flash units from Nikon and Canon seemingly having HUGE Guide Number advantages over the $450 Pentax flash I just got..
what I read was:
Canon 580EX - GN of 180 @ ISO 100
Nikon SB-800 - GN of 125 @ ISO 100
Pentax AF540FGZ - GN of 54 @ ISO 100
I panicked. Why is Pentax so LOW!?!?!?!?
Then, after some frantic searching, I found the cause.
The Pentax is the only one giving the Guide Number in *METERS*.
The other two are in Feet. HAH.
Crazy people and their feet. :P Making your stuff sound *SOOO* impressive.
Some of the websites give Canon's in meters too.. which is 58. (60 if you go by 3 ft/m exactly.)
Why would you go by 3ft/m exactly when it's 39.37in/m?
Actually the foot is now officially defined in terms of metric units as being 0.3048 meters.
BTW, the metre is defined as the length of the path traveled by light in vacuum during a time interval of 1/299,792,458 of a second. This definition assumes that the speed of light is a constant 299,792,458 metres/second.
Actually the foot is now officially defined in terms of metric units as being 0.3048 meters.
BTW, the metre is defined as the length of the path traveled by light in vacuum during a time interval of 1/299,792,458 of a second. This definition assumes that the speed of light is a constant 299,792,458 metres/second.
Actually the foot is now officially defined in terms of metric units as being 0.3048 meters.
BTW, the metre is defined as the length of the path traveled by light in vacuum during a time interval of 1/299,792,458 of a second. This definition assumes that the speed of light is a constant 299,792,458 metres/second.
