Canon 580EX - Manual (Page 25)

Displayed Flash Output Figures
When you change the flash oulpul during shooting, the table below makes it
easier to see how the stop changes such as 1/2 -0.3
1/2 -» 1/2 +0.3. You
can see how the stop changes when you increase or decrease the flash
output.
For example, when you decrease the flash output to 1/2,1/2 -0.3, or 1/2 -0.7,
and then Increase the flash output to more than 1/2, 1/2 +0.3,1/2 +0,7, and
1/1 will be displayed.
Sample Flash Output Figures
Figures for decreased flash output -*
1/1 1/1 -0.3 1/1 -0.7
1/2 +0.7 1/2 +0.3
1/2 1/2 -0.3
1/4 +0.7
1/2 -0.7
1/4+0.3
1/4
i- Figures for increased Hash output
I
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