New Guide Number calculator

WayneF

Senior Member
I just put a new Guide Number calculator on my page about Guide Number,
at Understanding Guide Numbers

It does the math to convert one Guide number (at full power level) at some ISO,

to a new guide number at another ISO and/or another power level.

It assumes still the same zoom (same angular coverage). As an approximation, coverage diameter half of what it was should be 1.414x higher Guide Number, but sometimes reflector details are unknown and not linear.

The calculator can work from any ISO baseline, it doesn't have to be ISO 100, but I suspect there is not much use for anything but ISO 100. :)
 
Last edited:

WayneF

Senior Member
I have added a few enhancements to make the Guide Number calculator be rather versatile (and fully accurate). It does cover a few situations.

Understanding Guide Numbers

I would be interested in hearing comments about how the additional details might suffer from not being understandable enough to use? The goal was to be very obvious, but additional uses do involve details. Thanks, Wayne
 
Last edited:
Top