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 VS20 and Panasonic GX9 side-by-side from the front, back and top in their relative dimensions. Pentax VS20 has external dimensions of 111 x 61 x 38 mm (4.37 x 2.4 x 1.5″) and weighs 235 g (0.52 lb / 8.29 oz) (including batteries). Panasonic GX9 has external dimensions of 124 x 72 x 47 mm (4.88 x 2.83 x 1.85″) and weighs 450 g (0.99 lb / 14.36 oz) (including batteries).
Below you can see the front-view size comparison of the Pentax VS20 and the Panasonic GX9. Pentax VS20 is clearly the smaller of the two cameras. Its body is 13mm narrower, 11mm shorter and 9mm thinner than Panasonic GX9. As you can tell, actually this is not a fair size comparison since Pentax VS20 has a built-in lens but Panasonic GX9 doesn't. Once you put a lens on GX9, its thickness will increase significantly.
Here is the back view size comparison of the Pentax VS20 and Panasonic GX9.
Now lets look at the top view comparison of Pentax VS20 and Panasonic GX9.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Pentax VS20 is significantly lighter (215g ) than the Panasonic GX9 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 GX9, the total kit will weigh much higher.
Weather Sealing
Unfortunately neither the Pentax Optio VS20 nor Panasonic Lumix DC-GX9 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 Top Mirrorless Cameras with Weather Sealing
LCD Screen Size and Features
Pentax VS20 and Panasonic GX9's LCD screens have the same diagonal size of 3.00 inches.
On the other hand, Panasonic GX9 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 VS20 has a fixed type screen which provides less flexibility in shooting positions compared to GX9.