OR just look at your digital readout.
If your highlights are blinking turn your flash down. If things are
dark, turn it up.
You can do this without knowing anything about guide numbers. Flash
can be as easy as reading your histogram.
Give me some time, I'll write out how I do it.
It really is super simple once you get the hang of it.
Lea
On Jan 6, 2009, at 6:02 PM, karl shah-jenner wrote:
Re: Flash Unit
Ok. Give me some time to get it written out.
two words - guide number (!)
once you learn how the guide number of the flash or flash& diffusor
works, the rest falls into place pretty quickly.
say you have a GN of 60 (metric) for 100 ISO (which is the same as
GN 45 for 50 ISO, 90 for ISO 200, 120 for 400, etc <think stops>)
divide the GN by the distance to obtain the correct aperture f stop
number
or
divide the GN by the aperture to get the right distance to set your
subject :)
60 / 6m .. aperture = f11
60/ 2m .. aperture = f32
60 at half power (GN is now 30)
30 / 6m = aperture = 4.5 or 5.6
30 / 2m aperture = f16
(note you'd be best advised to TEST 1/2 and 1/4 settings to find the
actual GN rather than the stated one then write it on the flash head
for later reference.
k
babies. they're what i do.
www.leamurphy.com
