A professional flash or a professional speedlight completes the bag of a professional photographer. Pro Street Photographers, photo journalists, professional nature photographer & professional studio photographers always use flashes & speed lights to a varying degree in their images.
Pro Nikon Flash – SB 600

The flash features i-TTL control as part of the new Creative Lighting System (CLS), being introduced with the D2H digital SLR camera. The new i-TTL system supports Advanced Wireless Lighting and versatile functions for up to four groups of Speedlights, with 3 remote i-TTL speedlight groups controlled through the master SB-800 or with the “Commander” function.
Buy it from Adorama Photo or BH Photo.
Nikon SB-900 AF Speedlight i-TTL Shoe Mount Flash

The Nikon SB-900 Speedlight is one of the most advanced pro flash in the Speedlight range. It’s automated zoom head has been expanded to cover 17mm to 200mm lenses (in 35mm/FX format), and can cover this range in just 1.2 seconds. This flash now lets you select from three light distribution patterns: Standard, Center-weighted, and Even. It will also automatically detect if it is connected to a DX or FX format camera, and adjust itself accordingly.
The SB-900 can work as a stand-alone flash, or as part of a wireless group, either in Commander mode or as a slave (remote). The i-TTL system in this flash supports Advanced Wireless Lighting and versatile functions for up to four groups of Speedlights, with 3 remote i-TTL Speedlight groups controlled through the master SB-900.
Buy it from Adorama Photo or BH Photo.

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[...] F100 Pro Photography CameraNikon F5 Pro Photography CameraNikon F6 Pro Photography CameraProfessional Flash & Speedlights for Pro PhotographyStreet Photographer Camera BagZeiss Ikon Pro Street Photography CameraProPhoto Tutorials Guides [...]
[...] F100 Pro Photography CameraNikon F5 Pro Photography CameraNikon F6 Pro Photography CameraProfessional Flash & Speedlights for Pro PhotographyStreet Photographer Camera BagZeiss Ikon Pro Street Photography CameraTutorials & GuidesComputer [...]
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