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-3 and Olympus E-M1 side-by-side from the front, back and top in their relative dimensions. Pentax WG-3 has external dimensions of 124 x 64 x 33 mm (4.9 x 2.5 x 1.3″) and weighs 230 g (0.51 lb / 8.11 oz) (including batteries). Olympus E-M1 has external dimensions of 130 x 94 x 63 mm (5.13 x 3.68 x 2.48″) and weighs 497 g (1.10 lb / 17.53 oz) (including batteries).
Below you can see the front-view size comparison of the Pentax WG-3 and the Olympus E-M1. Pentax WG-3 is clearly the smaller of the two cameras. Its body is 6mm narrower, 30mm shorter and 30mm thinner than Olympus E-M1. As you can tell, actually this is not a fair size comparison since Pentax WG-3 has a built-in lens but Olympus E-M1 doesn't. Once you put a lens on E-M1, its thickness will increase significantly.
Here is the back view size comparison of the Pentax WG-3 and Olympus E-M1.
Now lets look at the top view comparison of Pentax WG-3 and Olympus E-M1.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Pentax WG-3 is significantly lighter (267g ) than the Olympus E-M1 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 E-M1, the total kit will weigh much higher.
Weather Sealing
LCD Screen Size and Features
Pentax WG-3 and Olympus E-M1's LCD screens have the same diagonal size of 3.00 inches.
On the other hand, Olympus E-M1 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-3 has a fixed type screen which provides less flexibility in shooting positions compared to E-M1.