Size and weight are big decision factors when you are trying to find the ideal camera for your needs.
In this section, we are going to illustrate the Pentax X-5 and Nikon D90 side-by-side from the front, back and top in their relative dimensions. Pentax X-5 has external dimensions of 119 x 86 x 107 mm (4.69 x 3.39 x 4.21″) and weighs 595 g (1.31 lb / 20.99 oz) (including batteries). Nikon D90 has external dimensions of 132 x 103 x 77 mm (5.2 x 4.06 x 3.03″) and weighs 703 g (1.55 lb / 24.80 oz) (including batteries).
Below you can see the front-view size comparison of the Pentax X-5 and the Nikon D90. Pentax X-5 is 13mm narrower and 17mm shorter than Nikon D90 but it is also 30mm thicker. As you can tell, actually this is not a fair size comparison since Pentax X-5 has a built-in lens but Nikon D90 doesn't. Once you put a lens on D90, its thickness will increase significantly.
Now lets look at the top view comparison of Pentax X-5 and Nikon D90.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Pentax X-5 is significantly lighter (108g ) than the Nikon D90 which may become a big advantage especially on long walking trips.
Again, this comparison may not be very useful in real life as we are comparing the weight of a camera with a built-in lens to the body-only weight of an interchangeable lens camera. Once you put a lens on D90, the total kit will weigh much higher.
Weather Sealing
Unfortunately neither the Pentax X-5 nor Nikon D90 provides any type of weather sealing in their bodies, so you have to give extra care especially when you are shooting outdoors. If weather sealing is a must-have feature for you, check these sections: Top Bridge Cameras with Weather Sealing Top DSLR Cameras with Weather Sealing
LCD Screen Size and Features
Pentax X-5 and Nikon D90's LCD screens have the same diagonal size of 3.00 inches.
On the other hand, Pentax X-5 features a
Tilting screen where you can change the angle of the screen to make it easier to shoot from waist or over-the-head levels whereas the Nikon D90 has a fixed type screen which provides less flexibility in shooting positions compared to X-5.