I would like to know about the light emission characteristics of speedlite 600ex-rt.

[ErikL]

What is the intensity of light as a function of time? What is the ignition time? What is the color temperature? Can you recommend some literature on the basics of flash light?

[Mykolas]

Hi ErikL,

All of the specifications that are available are listed on our website.  Please refer to the link below:

http://www.usa.canon.com/cusa/consumer/products/cameras/speedlite_flash_lineup/speedlite_600ex_rt

When you reach the website using the link above, click on [Specifications].  You can also click on [Brochures & Manuals] and download the instruction manual for the flash, which also has a number of specifications listed in it.

[Skirball]

I don't think there's a lot of technical information in those specs.  And most of these questions aren't straight forward.

Easiest first, the color temp is around 5500-6000K, a little cooler than sunlight and will vary depending on power.

The flash duration is a bit more vague and depends on when you draw the line (consider it to be off).  It can change the specs significantly.  The full power spec from Canon puts it at about 1/800 for the 580exII, but anyone who has tried to freeze motion at full power will tell you that's false.  I find it to be more like 1/200.  You can losely extrapolate the lower power times as flashes simply double duration to double power.

Actually, I found this website that has some info on the 580II durations, which should get you in the ballpark for the 600.

http://speedlights.net/2011/04/18/canon-speedlite-580ex-ii-flash-review/

And David Hobby had a great article on it at Strobist:

http://strobist.blogspot.com/2010/06/rise-and-fall-of-machines-understanding.html

There's even more technical discussions you can dig up if interested.