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12-09-2012, 11:41 AM   #1
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Flash problem on power 1/1, 1/2

I need your help. I'm a beginner with strobes and I don't understand one thing: with this settings (iso100,1/180,f8) and a flash in slave mode, I obtain complete dark pictures if the flash is set on 1/2 or 1/1. With other powers it works. I don't understand it!
The flash is controlled in wireless mode with the built-in flash of my k5 (and i've also tried both the options to use the built in flash as a master or not (MENU/C3/21).
The subject was 1 meter away in front of the camera and the flash was set on the left of the camera.
Can you explain me where I mistake?

Thank you very much!

Last edited by gabro822; 12-09-2012 at 12:08 PM.
12-09-2012, 12:55 PM   #2
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Does the flash trigger correctly?
Sounds to me the flash is going of with the "pre-flash" for the P-TTL metering and not with the main flash.

Also is your shutterspeed really 1/180 because 1/180 is not a "normal" shutterspeed you can get to.
12-09-2012, 02:53 PM   #3

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Read this:

12-09-2012, 05:34 PM   #4
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Hi all! Yes, the shutter speed is 180, since I set 1/200 in manual mode, but when I pop-up the built in flash it automatically change the shutter speed to 1/180!

I didn't know about the preflash of the built-in flash for pttl! I mean, I thought that if I set the on-camera flash to wireless mode, it only controls the slave flash and doesn't have any influence in the scene.
So when I shot at 1/32 of the power, the flash has the time to recharge and fire again?! I really didn't thought!
Is there any way to block the pre-flash?

Thank you very much for the explanation!

12-09-2012, 09:22 PM   #5

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Read this post (and the threads it refers to) for explanations as what happens when the built-in flash is set to wireless mode.

Note that in your case, the remove flash is triggered by any strobe from any source.

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