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12-21-2011, 06:16 AM   #1
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500-FTZ as optical slave question

I recently acquired a used 500-FTZ.for a really cheap price. I've been exploring the options of using it off camera and using the optical slave function. Recently I was testing it out with a friend for a family portrait. It fires every time regardless of the setting, but I noticed that when the output was 1/1 or 1/2 power it didn't fire during the exposure. From 1/4 power to 1/32 power it worked fine.

Does anyone know if there's a reason for this? To summarize... at 1/1 or 1/2 it fires, but not exactly while the shutter is open. Aside from changing the flash power output, ALL camera and flash settings were otherwise the same.

12-21-2011, 07:14 AM   #2
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If you are using the on board flash of a k-series digital body to trigger it, the onboard flash fires twice. Once for pttl computation, the second is synced with the shutter. The first sets off the other flash before the shutter is open and on a high power setting, the flash doesn't recycle fast enough for the second flash. You need an optical slave that will ignore preflash or I believe (but not 100% sure) the onboard flash doesn't use pttl if in M mode so it might work fine then.
12-21-2011, 11:03 AM   #3
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Hi PANGU_yien,

I also use the 500-FTZ as an optical slave. If you have another flash unit handy, you can mount it on the camera and fire in manual. It will fire only once.

I use a *ist D, so sometimes I use the AF400TZ mounted on the camera in TTL mode. But I think this wont work with later bodies, which is keeping me from upgrading.

12-21-2011, 07:34 PM   #4
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Hal it will work on most *istD series bodies, I use mine in an *istS too


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