Size and weight is a big decision factor when you are trying to find the ideal camera for your needs.
In this section, We are going to illustrate Nikon D3X and Nikon D5 side-by-side from the front, back and top in their relative dimensions. Nikon D3X has external dimensions of 160 x 157 x 88 mm (6.3 x 6.18 x 3.46″) and weighs 1260 g (2.78 lb / 44.45 oz) (including batteries). Nikon D5 has external dimensions of 160 x 158.5 x 92 mm (6.3 x 6.2 x 3.62″) and weighs 1415 g (3.12 lb / 49.91 oz) (including batteries).
Below you can see the front view size comparison of Nikon D3X and Nikon D5. Nikon D3X has the same height with Nikon D5. On the other hand, with a width of 157mm, it is 2 narrower and also with a thickness of 88mm, it is 4mm thinner than Nikon D5.
Here is the back view size comparison of Nikon D3X and Nikon D5.
Now lets look at the top view comparison of Nikon D3X and Nikon D5.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Nikon D3X is 155g lighter than the Nikon D5 but we don't think this will make a significant difference.
Also keep in mind that body weight is not the only deciding factor when comparing two interchangeable camera bodies, you have to also take into account the lenses that you will be using with these bodies. Since both Nikon D3X and Nikon D5 have the same Nikon F lens mount and Full frame sized sensors, lenses will not be a differentiator on total size of the system.
Both D3X and D5 have weather sealings in their body, making them resistant to water and dust.
LCD Screen Size and Features
Nikon D5's 3.2" LCD screen is slightly larger than Nikon D3X's 3" screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.