Nikon D700 shares many components from D3 like the 12.1 megapixel CMOS full-frame sensor, Multi-CAM3500FX Auto Focus sensor and EXPEED image processor but lacks some of the features as expected considering the price difference. But there are also still things you get over D3 like vibration based dust reduction, expanded function button and built-in flash.

ALERT!

Below is a quick comparison of Nikon D700 and D3:

Built-in Flash
Nikon D700 has a Built-in Flash (iTTL, G.No 17/ISO 200), D3 doesn't. (Some people think that a pro level DSLR shouln't have built-in flash, I totally disagree with them)

LCD Screen
Nikon D700 doesn't have a rear LCD panel. (Not a big loss in my opinion)

Viewfinder
D700:95% coverage, 0.72x magnification viewfinder vs. D3: 100% / 0.7x magnification. Honestly, %95 coverage is a little disappointment for me. (Viewfinder has always been an important deciding point in this level)

Burst Rate
D700: 5.0 fps (8.0 fps with optional MB-D10), D3: 9 fps (11 fps without AF). I don't understand why it is slower then D300, the files sizes should be the same

Shutter life
D700:150,000 cycle, D3: 300,000 cycle

Memory Slots
Nikon D3 has single CF slot while D3 has two

Dust Reduction
D700 features a sensor shake dust reduction (big advantage here for D700, hope it works fine)

Focus Screen
DX Mode Focus screen on D700 is indicated with rectangle, on D3 it is indicated with a shaded area

Function Buttons
Function button on D700 is expanded compared to D3, all the menu items can be assigned to Function button. (another point for D700)

Weight
D700: 995g, D3: 1240g

Live View
Live View on D700 can be assigned to FUNC, AE-L or Preview buttons

Price: D700: $2.999, D3: $4.999

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