John Deerfield wrote:
5 As pointed out, it is only 1/6 of a stop difference. If you are worried about metering to the 1/10th of a stop for establishing ratios, I might suggest that there are better lights out there. Otherwise, without metering, I am not sure I could even see a 1/6 of a stop difference.
No. It was pointed out that there was a 1/6 of a stop difference between a single 580EX II and two 430EX II Speedlites mounted to operate in tandem.
580EX II and a
430EX II the power difference is about 9/10 of a stop. That's an awkward difference when computing ratios.
– gisle [ See profile/plan for equipment list ]