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 Panasonic S1 and Fujifilm X20 side-by-side from the front, back and top in their relative dimensions. Panasonic S1 has external dimensions of 99 x 59 x 21 mm (3.9 x 2.32 x 0.83″) and weighs 117 g (0.26 lb / 4.13 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 Panasonic S1 and the Fujifilm X20. Panasonic S1 is clearly the smaller of the two cameras. Its body is 18mm narrower, 11mm shorter and 36mm thinner than Fujifilm X20.
Here is the back view size comparison of the Panasonic S1 and Fujifilm X20.
Now lets look at the top view comparison of Panasonic S1 and Fujifilm X20.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Panasonic S1 is significantly lighter (236g ) than the Fujifilm X20 which may become a big advantage especially on long walking trips.
Weather Sealing
Unfortunately neither the Panasonic Lumix DMC-S1 nor Fujifilm X20 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 Compact Cameras with Weather Sealing
LCD Screen Size and Features
Fujifilm X20's 2.80" LCD screen is slightly larger than Panasonic S1's 2.7 screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.