Manual Flash

Marc

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If I use my flashgun on Manual, what is the method of deciding which level to use? (ie, 1/1, 1/2, 1/4, 1/8 etc...) or is it just a case of do test shots first, then trial and error?
 
The latter. Dropping the power by a half lowers the light by one stop. Its really just the same as +/- flash compensation
 
either invest in a light meter or use the suck-it-and-see method.

Easiest way is to start at say 1/4 power, fire off a shot and then adjust the power up or down as needed.
 
Cheer guys.

Looks like the suck-it-and-see method then. May add a light meter to the Christmas list, any recommendations that won't have the missus saying "I'M NOT BUYING YOU THAT!" ? :D
 
Cheer guys.

Looks like the suck-it-and-see method then. May add a light meter to the Christmas list, any recommendations that won't have the missus saying "I'M NOT BUYING YOU THAT!" ? :D


No :LOL: A Sekonic 308s is about the cheapest decent one at £125 new
 
ok, so at full power if the flash has a GN of 58 (ft or m?) you can calculate what aperture to use by using the equation fstop = GN/distance
 
for example if the subject is 15ft away you would do 58/15 = 3.87 ~ f/4

this is a very simplified version, as you have to take into account the film speed and the GN changes as you reduce the power of the flash - 1/2 power would not just be 58/2 though.
 
Thanks ruvor. I think I managed to understand that. :)
 
your best bet is to just google 'guide number equations' as I'm sure there will be a better more comprehensive explanation out there. I used to use them all the time, but have gotten lazy since I bought my meter (sekonic L358) about a year ago.
 
I've got a L-358 as my light meter. Very very good buy that was!!! Get one of those ;)

As for manual power of your flashes I just do it depending on what the natural lighting is like and if your wanting a more natural flash look to match the ambient or if your wanting to just have the light from the flashes.

Bright sunny days - 1/1 or 1/2
Overcast - 1/2 or 1/4 (depending on the effect and lighting I'm going for)
Night - 1/2 or 1/4

Then change the light spread as well, so if you want a more direct light on your subject or a wide light spread.

Well thats what I do in my skateboarding shots anyway. It's just a matter of trying and seeing really
 
Cheers. I think the 358 might earn me a kick in the proverbials, but the 308 might just be in range. (y)
 
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