I shot this iPhone pic of my assistant Jon as we were setting up for an exterior portrait shoot. I didn't realize until later how funny the picture turned out, as it appears that Jon unwittingly became a conductor of electricity.

When using strobes outside in full sunlight you can run into problems. The prominent issue is the fast shutter speed and high "f" number required to make a decent exposure. It is best to use manual exposure mode for shoots like this, with your shutter speed set to 1/200. This number is a safe average of most camera shutter sync speeds. If you have a faster shutter speed than what your camera is made to handle, the strobe or flash will have no effect.
Next, your aperture, or "f" number will probably be quite high because of the locked shutter speed of 1/200 and the bright daylight. You may find that the proper exposure is f8, or f14. This can be a problem because when the aperture number increases, less light is available from the flash/strobe to the subject. It is not that the flash or strobe becomes weaker, rather it takes a more powerful flash to counteract the smaller lens opening.
If you find that you need more flash power even though it is broad daylight, but you are at max power on your flash or strobe, then try these techniques:
Use a polarizing filter on your lens. This will drop your aperture f-number down approximately two stops (depending on the type of polarizer). When you use a lower f-number there will be more effective light power traveling from the source to the subject.
Another option is to simply place the lights closer to the subject. This instruction may seem laughable due to its obvious nature, but many new photographers do not realize that effective light power increases when the distance between light source and subject decreases.
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