Please I need to know ASAP how I can remove the repeating flash? Each time I try to use the trigger flash, the flash make two or three flashlights before the main flashlight. I didn't find anything about this in the manual. Please, anyone can help me? Thank you so much.
I think you must have Red Eye Reduction turned on, which does that. It first flashes 2 or 3 times in one second (trying to reduce the size of the subjects eye pupil), before the shutter opens and the full flash fires. This is in the flash sync menu, in the D7000 User Manual on page 144 and 145 (or search the index for Red Eye Reduction). The correct default mode is Fill Flash mode, which simply means regular front curtain sync (the Nikon metering system default is fill flash either way). Red Eye Reduction is more intrusive than helpful, turn that off.