Why is the bottom half my picture black when shooting with Cowboy Studio remote triggers?

  • This is my very first day of shooting with flash and remote flash. And picture turned out like this: Bottom half of it is black. I have no idea what has caused this and how to prevent it? I just know that after this I shot a few more frames without flash or only with the camera's built-in flash and they were fine so I know the camera is not broken. When I read the photo EXIF info this is what I had: 1/400 sec with f 2.8 and 60mm. My flash is a manual flash and its power was on 1/32 and zoom on 70mm.
    No specific reason for these numbers, I was only experimenting. Also I had set the exposure compensation of the camera to -5.00 in the hope that it would make the background darker and the foreground look more 3D because of the flash.

    Also my off camera flash was wirelessly firing with Cowboy Studio remote triggers. Could that be it?

  • D. Lambert

    D. Lambert Correct answer

    6 years ago

    You're shooting with a shutter speed faster than your sync speed (most likely 1/200 or 1/250). Your camera's shutter consists of two curtains -- the first one opens to begin the exposure, and the second follows it -- closing to end the exposure. At speeds slower than your camera's sync speed, these two curtain movements allow at least a tiny fraction of time between opening and closing, but at faster shutter speeds, the closing curtain is actually chasing the opening curtain, creating a moving slit of exposure. A flash occurring during such an exposure is only going to illuminate part of the sensor - hence, the dark bar.

    This is a bit tricky to picture, but this video shows exactly what's happening with those curtains:

    https://www.youtube.com/watch?v=CmjeCchGRQo

    Thanks, so as far as how to make sure this doesn't happen, I should always make sure when taking pics with flash, my shutter speed should be faster than 1/250?

    Check the flash sync speed of your camera - it's likely 1/200 or 1/250. It's possible to go faster than that with a flash capable of High Speed Sync, but that won't be an option with a manual flash.

    Also, I've encountered minor lag with radio triggers when on the fastest sync speed before and so I often dial it back a touch to account for it. The better the trigger quality, the less this is likely to happen.

    @Blake You need to make sure the shutter speed is either at the sync speed or *slower*.

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Content dated before 7/24/2021 11:53 AM