Strength of different flash units

[elyshiamadison]

I think something finally "flashed" in my head late last night, after reading up on Speedlights.net (http://speedlights.net) that would kind of make sense as to why my shots are coming across with such flat / even light! And feeling a little silly if I am right!

Basically I am using 2 flash units in brolly's, if those 2 flash units have different guide numbers (for example I have been using my Metz 48 (GN 29) at 1/8 or even 1/4 as my key light, and a Yonghuno 560 (GN 39) at say 1/64 or even 1/128) That would more or less give even light wouldn't it? (I've guessed an example setting - so please bear that in mind - and I am only very new to this!)

I really SHOULD be using my YN560 as my main and the Metz as my fill shouldn't I??? I've tried many combinations of power settings, and without pumping out 1/2 or 1/1 through the metz I'm not having much luck creating the fill effect. Which sucks the power pretty quickly!

I will try it tonight, but is my thinking more on track if I swap the flash used for fill to the key? Of course then I would have to adapt the power settings of each flash gun....

Oh I hope this makes sense, because I am a little lost now lol... So much so that I'm waiting on studio strobes to arrive thinking I would be able to learn to light better with those! It won't be a waste, they will get used, but I could have saved some cash!

[I @ M]

I never was any good at mathematics so trying to work out guide numbers and power settings is al too much for me. :(

A light meter gives you the answer at the push of a button, is easily transported when you go on "location" with your speedlights and is very handy in a studio situation for measuring light at different parts of the composition. They aren't all that expensive and seem to be pretty reliable over a long time period.:)

[kiwi]

The distance to subject is also relevant

If you are aiming at say a 1:3 traditional lighting ratio and if one flash is more powerful than another then yes, yiu have to take this into account. I don't think it really matters what flash is which as long as you can work out the ratios and guide numbers and subsequent lighting power settings,

[elyshiamadison]

Yes I think a light meter will be in my xmas wish list! I priced them the other day their not too bad.... oh well lenses will be later :(

Thanks Kiwi, I will give it a go and swap the main for the fill and see if I have any luck..... it's starting to do my head in (because I am NO good at maths either lol) hopefully it will make it easier for me to guage the light until I get a light meter!