please help

went to B&H on sunday and picked up a SP Excalibur 3200 studio strobe Kit http://www.bhphotovide​o.com …ails&Q=&sku=129​711&is=REG ..ok here's my problem i get different results when i use the slave sensor vs the pc cord . when i use the pc cord i get overexposed photo's vs when i use the slave sensor. should i be getting the same results if i use either one, or by using the cord on the camera is it sending different info to the strobe, and is there a delay when i use it with the slave sensor vs the pc cord causing this problem.i have to use different camera settings when i use either setup..using 10D / 24-70mm 2.8L .. what am i doing wrong please help

What are you using to trip the slave sensor? What mode is your camera set on--manual, I hope. Do you have a flash meter?

580 flash to trip slave sensor . yes manual mode . no meter

Well, I'm puzzled. Is the 580 on when you use the synch cord? And how is the on-camera flash set?

I wish you had a meter, so you could tell if it's the strobe doing something different, or if it's something with the camera/flash.

the 580 is not on when i use the synch cord. i also wish i had a meter

It sounds like E-TTL is activated which is firing the stobe with the E-TTL pre flash. Set your 580 to the manual setting and see if this solves the problem.

I guess you could try turning the 580 on (to the same setting as when using the slave) when you use the synch cord and see if things level out. I'm sure you're flipping the slave/synch switch on the monolight to the appropriate position?

(Assuming the 580EX is on manual) It could be your shuttertime is too fast to enable the entire power of the flash system to expose the frame.(because the slave cell is slower than the sync) Then again, you should see a gradient across the frame. Try setting 1/60

when i use the pc cord the 580 is not on the camera so it cant be the pre flash ..when i set the shutter speed to 1/60 my expose meter goes all the way too the left. so what your saying is when i use the slave vs pc cord the reaction time is slower. can this be my problem (timing) does this make any sences.sorry for sounding so dumb but iam trying really hard to learn ..

thank you
luis

If you are getting overexposure with the PC cord (sync triggered) and proper exposure using the 580 (slave triggered) using the same settings (shutter speed and aperture) then what could be happening is the pre flash from the 580 is triggering the strobes to soon. The only light your camera is seeing when the photo is taken is from the 580 flash giving you proper exposure for those setting (aperture and shutter speed). When you use the PC cord and the same settings (aperture and shutter speed) you would get over exposure because the strobe is more powerful than the 580. If you set the 580 to manual, there will be no pre flash thus no pre triggering of the strobes and the camera will see the strobes instead of just the 580. Then the results should be fairly close using either method and the same aperture and shutter speed.

Luis, when you're using a monolight like this your in-camera meter is irrelevant because it isn't reading the light from the monolight, except when the on-camera flash is set to an auto function, and then, as has been said, the pre-flash may play havoc with the metering.

As Wolf said, the flash on-camera should be on a manual setting. I would set it to a low power setting so it's just enough to trip the slaved monolight, but not powerful enough to add much light to the subject, unless you want to use it for fill-in or as part of the lighting set-up.

Other than the exposure, did the lighting in the pictures you've made with the different methods of tripping the monolight look different? In other words, if you're using the monolight off to one side, did both methods look like they were lit from the side, or did one look side-lit while the other like it was front lit (from the on-camera flash)?

You probably don't want to hear this, but you should really invest in a flash meter for using lights that aren't regulated by the camera's system. I can't even imagine guessing at exposures with studio strobes.

Your 580EX should have a "M" indicator. And the ETTL should disappear. This is the manual mode for the 580EX. If the ETTL is on, the pre-flash will prematurely fire the monolights. I have used these lights at a local photo place. They work perfectly fine, as long you know how to control them.

Just a note, I was able to trigger these strobe with the ST-E2. As long you cover the 4 contacts. Works great...

What? Why? That's what the histogram (and experience) is for. The beauty of DSLR (and polaroid for that matter ) is, you don't *need* a flashmeter. (Although it's easier to have one). I've worked for years using studio flash, and the only times I've used a flashmeter, was when doing repros.... Otherwise I'm never off more than 1/2 stop . . .

René Damkot wrote:
What? Why? That's what the histogram (and experience) is for. The beauty of DSLR (and polaroid for that matter ) is, you don't *need* a flashmeter. (Although it's easier to have one). I've worked for years using studio flash, and the only times I've used a flashmeter, was when doing repros.... Otherwise I'm never off more than 1/2 stop . . .

You must be a quite an exceptional master of light. You're going to tell me you are always within 1/2 stop when using different light modifiers and multiple light setups with a variety of subject sizes and varying distance of light to subject and varied power outputs to different lights? Forgive me if I don't believe you.

I'll grant you that you can fiddle around with the histogram, and that much experience can get you closer to a correct exposure than little experience, but a light meter eliminates the guesswork and fiddling about, and it's much easier to determine lighting ratios with a meter than it is to play guess-o-matic.

You weren't using color negative film for these 1/2-stop guesstimates, were you?

Nope, polaroid & slide film on H'blad. Off course the 'guesstimation' I reffered to was when using a more or less known setup (portrait session for instance). When out of the studio on location, or out in the open, a light meter was used (or lots of polaroids )
I agree using a light meter makes life much easier, but I don't think one *must* have one. Also, you know what a flash heads light output is at a given power setting and distance, so calculating what it will be at another setting or distance isn't that complicated.