canon flash system: ratios?

Forgot about umbrella's!

Thanks again for your help its much appreciated.

wait, im confused now. if i had my ratios set properly, why would my 430ex be more powerful than my 580ex?

PacAce wrote in post #4582436
Yes, you can. AAMOF, that is exactly how I would do it. In this setup, though, the slaves have to be in ETTL mode. The other option is to set the slaves to Manual mode and then adjust the slave power individually on each slave. All the master needs to do in this case, then, is to just trigger them.

So what you are proposing is I put the Slaves in ETTL and then control them via ratio? And the main flash unit via exposure compensation? I prefer to have manual control of all 3 so would I then put all 3 in manual mode and just control the flashes via the A:B:C mode

Here is a picture I took using that technique last night. BTW the lens is also for sale in the classifieds forum.

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CanonXtiDude wrote in post #4583929
So what you are proposing is I put the Slaves in ETTL and then control them via ratio? And the main flash unit via exposure compensation? I prefer to have manual control of all 3 so would I then put all 3 in manual mode and just control the flashes via the A:B:C mode

Here is a picture I took using that technique last night. BTW the lens is also for sale in the classifieds forum.

http://farm3.static.fl​ickr.com …2143514766_ff4a​26f9ae.jpg

Although you are using the "ratio" feature, you're not actually setting the ratio when the master is in Manual mode. What you are doing is setting the actual power output, i.e. 1/1, 1/2, 1/4, etc., of the master and individual slaves. When the slaves are set to ETTL mode, you adjust the slave output from the master itself. When you set the slaves to Manual mode, you have to go to each slave and adjust its output. So, whether the slaves are in manual mode or ETTL mode, as long as the master is in Manual mode, all the slaves will operate in manual mode which you have full control over. The difference is how the outputs of the slaves are adjusted.

e r y k wrote in post #4583241
wait, im confused now. if i had my ratios set properly, why would my 430ex be more powerful than my 580ex?

Ordinarily, the master that's on the camera is used as the fill light and the slave off to one side is used as the key or main light. So, that means, by definition, that the slave output will be more intense than the master output.

PacAce wrote in post #4584173
Although you are using the "ratio" feature, you're not actually setting the ratio when the master is in Manual mode. What you are doing is setting the actual power output, i.e. 1/1, 1/2, 1/4, etc., of the master and individual slaves. When the slaves are set to ETTL mode, you adjust the slave output from the master itself. When you set the slaves to Manual mode, you have to go to each slave and adjust its output. So, whether the slaves are in manual mode or ETTL mode, as long as the master is in Manual mode, all the slaves will operate in manual mode which you have full control over. The difference is how the outputs of the slaves are adjusted.

I am not sure if you can be as precise with the ratio mode. You can add in 1/3 stop increments on manual.

CanonXtiDude wrote in post #4584202
I am not sure if you can be as precise with the ratio mode. You can add in 1/3 stop increments on manual.

I think you misunderstood my previous post. I said that the slaves are set manually, not by ratio.

PacAce wrote in post #4584223
I think you misunderstood my previous post. I said that the slaves are set manually, not by ratio.

I think I just fried my 580EXII not sure though maybe you will have some thoughts on the matter. I was shooting on a cable and i put the flash between my legs to hold it with the lens of the flash in my jeans. I mistakenly hit the shutter and I heard the flash POOF and some smoke come out and a horrible smell. Then the flash didnt work. So I figured I blew the bulb and a 400$ flash but after a few seconds it started to work again. Now my question is are there more than two flash heads in the 580EX II and how would I know if one is blown? The flash seems to function correctly now.

There's is only one flash bulb in there so if you're seeing a flash, your flash is probably OK. Are you sure you didn't just burn your jeans?

PacAce wrote in post #4584195
Ordinarily, the master that's on the camera is used as the fill light and the slave off to one side is used as the key or main light. So, that means, by definition, that the slave output will be more intense than the master output.

is there any way to reverse this? ie ratios at 8:1 instead of 1:8? would that change the roles the flash plays?

e r y k wrote in post #4586041
is there any way to reverse this? ie ratios at 8:1 instead of 1:8? would that change the roles the flash plays?

Yes, you can. There is no reason why the master can't be the key light and the slave the fill using, say, a ratio of 8:1 as in your example, as long as the master is taken off the camera.

The only reason you don't want the master to be the key light when it's on the camera is because doing so would just produce an almost flat image with hardly any shadow areas. You will have brighter highlight areas, though, so maybe this setup will work well for a high-key image.

PacAce wrote in post #4586082
Yes, you can. There is no reason why the master can't be the key light and the slave the fill using, say, a ratio of 8:1 as in your example, as long as the master is taken off the camera.

The only reason you don't want the master to be the key light when it's on the camera is because doing so would just produce an almost flat image with hardly any shadow areas. You will have brighter highlight areas, though, so maybe this setup will work well for a high-key image.

I take back the part about the high-key image in my previous post. I thought about it a little bit more and it dawned on me that with the master on camera as the key light, the only time the fill would be noticeable is when the ratio is set to 1:1 (key = fill) or 2:1. At 4:1 and 8:1, the fill light output is relatively weak compared to that of the key that it won't be noticeable in the image. So, to effectively use the master as the key light, it would have to be taken off the camera and placed to one side or the other of the camera.

PacAce wrote in post #4586082
Yes, you can. There is no reason why the master can't be the key light and the slave the fill using, say, a ratio of 8:1 as in your example, as long as the master is taken off the camera.

The only reason you don't want the master to be the key light when it's on the camera is because doing so would just produce an almost flat image with hardly any shadow areas. You will have brighter highlight areas, though, so maybe this setup will work well for a high-key image.

thank you so much PacAce for the info

i remember watching jacobthephotographers video where he was shooting a model w/ the 580 on an offshoe cord, with the 430ex on a lightstand in the back. so it had to be possible :P

I'm not into off camera flash yet, but this thread was very informative...thanks.