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Fri Jan 09, 2015 12:07 am

Joined: Mon Dec 08, 2014 2:30 am
Posts: 3

I have 3 White Lightning Ultra 1200's. 200 ISO, 1/50th Shutter speed, shooting at 1.8. The white lightnings were custom built with a Canon brain, meaning that whenever I fire from my Canon 7D the flash will trigger all 3 units without a pocket wizard.

I've attached a beauty dish, an octabox, reflector, you name it - the camera doesn't pick up the strobe when it fires. I've taken photos with both the strobes on and off, there is barely any difference. You can tell slightly if you really look that there is a slight, slight difference in light. Shooting at full power, standing in front of an octabox - I would think that I'd be way overexposed at those settings. ALL THREE strobes are behaving this way. What gives?




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Fri Jan 09, 2015 12:28 am

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Joined: Tue Dec 08, 2009 11:49 am
Posts: 1432

Your camera's preflash is tripping the Ultra early so it fires way before the shutter is ready. You have to figure out how to turn off the camera's preflash. What's a WL with Canon brain? Nothing we ever made.




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Fri Jan 09, 2015 1:38 am

Joined: Mon Dec 08, 2014 2:30 am
Posts: 3

Luap wrote:
Your camera's preflash is tripping the Ultra early so it fires way before the shutter is ready. You have to figure out how to turn off the camera's preflash. What's a WL with Canon brain? Nothing we ever made.


Sorry, my english isn't that good. The WL's have triggers in them similar to whats inside the 580EX II. I can wirelessly trigger my white lightnings - When I am in my FLASH settings on the 7D I can hit the test button and all strobes will trigger without a problem.

http://www.learn.usa.canon.com/app/pdfs ... kGuide.pdf

http://learn.usa.canon.com/app/pdfs/qui ... kGuide.pdf


I am able to catch the light at 250 shutter speed in MULTI mode. However this isn't ideal, because the camera won't let me fire for at least 6 seconds since this is supposed to capture multiple pops off the strobe (like bulb mode).

I've turned off the AF assist pre-flash as mentioned here: http://www.scubaboard.com/forums/canon- ... oblem.html

My flash settings are:
Flash mode: Manual Flash
Shutter Sync:1st curtain
Wireless Func: Trigger off-camera Speedlites only
Channel: 1 Ch

I don't understand what is going on and why it would only work in MULTI mode




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Fri Jan 09, 2015 11:07 am

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Joined: Tue Dec 08, 2009 10:43 am
Posts: 5266

buddhadude wrote:
My flash settings are:
Flash mode: Manual Flash
Shutter Sync:1st curtain
Wireless Func: Trigger off-camera Speedlites only
Channel: 1 Ch

I don't understand what is going on and why it would only work in MULTI mode


The red settings are going to be the root cause of the issue. The Canon (and every other brand) optical wireless function works by sending a "Morse code" of light signals from the master flash to the slaved flashes. This all happens before the actual exposure, and Canon dedicated slave flashes know to wait a set amount of time before they flash so they go off during the actual exposure.

Additionally, any active TTL flash setting will have at least one flash before the exposure to determine what the camera thinks is proper exposure.

The White Lightning (and most other brand) studio flash units have "dumb" slaves that trigger when they see a flash, regardless of its purpose. So if you have a TTL preflash or a wireless command flash that goes off before the exposure, the WL will go off before the exposure, too, as it responds instantly, unaware that it is too early.

If the flash is set to a high-ish power, it will not have enough energy to go off with the exposure flash from the camera (assuming there is one). Sometimes, at lower powers, the light can recycle fast enough to fire again at the right time, but this is not optimal. If there is no flash during the exposure (like how you are set), then the flash will not fire at the right time, regardless of power setting.

Turn the 580 to M mode, and turn the wireless function off entirely. If needed, set it to fire during exposure. You can manually lower the flash power so that it does not affect the final image.




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