Light output from a strobe. Watt Seconds?

[Packhorse]

I think I read somewhere that strobes were rated in watt seconds in relation to the amount of light they put out.
Im a little confused by this as a watt is a measurement of power or power consumption and not light (like lumen or lux) and a strobe does not stay on for a second.

Anyway what I am more interested in is what type of light could you compare a 150 watt second strobe to in terms of light output for a similar beam angle.
eg is it equivalent to a 150 watt halogen (I realise that different 150watt halogens put out differing amounts of lumen) or perhaps a 50watt HID?
Can we convert watt seconds to lumen?

 

[gert7to3]

Here's a paper discussing the watts vs watts/sec question.
Keep in mind that watts are units of energy not light.

www.webs.lanset.com/rochran/flash/hotorstrobe.HTML

 

[gert7to3]

I'll check the link later. Still working out use of an iPod touch.
Try deleting the "www"

 

[Packhorse]

Thanks Gert. Still cant get a link to it. EDIT Here it is

Found this though.

 

[gert7to3]

That is essentially what the piece I found said.

An interesting topic, enjoy your summer.