The SB-800 has a slave mode called SU-4 in the menu. It activates remote flash. When your on camera flash fires so will the slave flash. The slave flash will need to be able to "see" the light from the on-camrea flash to work.
To access the SU-4 remote mode hold the "SEL" button in for a few seconds until the menu appears. Scroll down to the SU-4 setting and turn it on.
When using this method set the flash to manual and set the power as needed.
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The SB-800 has a slave mode called SU-4 in the menu. It activates remote flash. When your on camera flash fires so will the slave flash. The slave flash will need to be able to "see" the light from the on-camrea flash to work.
To access the SU-4 remote mode hold the "SEL" button in for a few seconds until the menu appears. Scroll down to the SU-4 setting and turn it on.
When using this method set the flash to manual and set the power as needed.