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 WG-2 and Sony A580 side-by-side from the front, back and top in their relative dimensions. Pentax WG-2 has external dimensions of 122 x 61 x 30 mm (4.8 x 2.4 x 1.18″) and weighs 192 g (0.42 lb / 6.77 oz) (including batteries). Sony A580 has external dimensions of 137 x 104 x 84 mm (5.39 x 4.09 x 3.31″) and weighs 599 g (1.32 lb / 21.13 oz) (including batteries).
Below you can see the front-view size comparison of the Pentax WG-2 and the Sony A580. Pentax WG-2 is clearly the smaller of the two cameras. Its body is 15mm narrower, 43mm shorter and 54mm thinner than Sony A580. As you can tell, actually this is not a fair size comparison since Pentax WG-2 has a built-in lens but Sony A580 doesn't. Once you put a lens on A580, its thickness will increase significantly.
Here is the back view size comparison of the Pentax WG-2 and Sony A580.
Now lets look at the top view comparison of Pentax WG-2 and Sony A580.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Pentax WG-2 is significantly lighter (407g ) than the Sony A580 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 A580, the total kit will weigh much higher.
Weather Sealing
Thanks to the weather-sealed body of the WG-2, you can use this camera with more confidence under conditions where there is risk of exposure to water and dust compared to the A580.
LCD Screen Size and Features
Pentax WG-2 and Sony A580's LCD screens have the same diagonal size of 3.00 inches.
On the other hand, Sony A580 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 Pentax WG-2 has a fixed type screen which provides less flexibility in shooting positions compared to A580.