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 Olympus E-M1 and Fujifilm X20 side-by-side from the front, back and top in their relative dimensions. 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). Fujifilm X20 has external dimensions of 117 x 70 x 57 mm (4.61 x 2.76 x 2.24″) and weighs 353 g (0.78 lb / 12.45 oz) (including batteries).
Below you can see the front-view size comparison of the Olympus E-M1 and the Fujifilm X20. Fujifilm X20 is clearly the smaller of the two cameras. Its body is 13mm narrower, 24mm shorter and 6mm thinner than Olympus E-M1. As you can tell, actually this is not a fair size comparison since Fujifilm X20 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 Olympus E-M1 and Fujifilm X20.
Now lets look at the top view comparison of Olympus E-M1 and Fujifilm X20.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Fujifilm X20 is significantly lighter (144g ) 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
With its weather-sealed body, we believe that the E-M1 has a big advantage over the X20 which doesn't provide any kind of environmental sealing.
LCD Screen Size and Features
Olympus E-M1's 3.00" LCD screen is slightly larger than Fujifilm X20's 2.8 screen.
In addition to the size advantage, Olympus E-M1 LCD screen also has a
Tilting feature where you can change the angle of the screen to make it easier to shoot from waist or over-the-head levels. On the other hand, Fujifilm X20 has a fixed type screen which provides less flexibility in shooting positions compared to E-M1.