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 ZS40 and Pentax RZ18 side-by-side from the front, back and top in their relative dimensions. Panasonic ZS40 has external dimensions of 111 x 64 x 34 mm (4.37 x 2.52 x 1.34″) and weighs 240 g (0.53 lb / 8.47 oz) (including batteries). Pentax RZ18 has external dimensions of 97 x 61 x 33 mm (3.82 x 2.4 x 1.3″) and weighs 178 g (0.39 lb / 6.28 oz) (including batteries).
Below you can see the front-view size comparison of the Panasonic ZS40 and the Pentax RZ18. Pentax RZ18 is clearly the smaller of the two cameras. Its body is 14mm narrower, 3mm shorter and 1mm thinner than Panasonic ZS40.
Here is the back view size comparison of the Panasonic ZS40 and Pentax RZ18.
Now lets look at the top view comparison of Panasonic ZS40 and Pentax RZ18.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Pentax RZ18 is significantly lighter (62g ) than the Panasonic ZS40 which may become a big advantage especially on long walking trips.
Weather Sealing
Thanks to the weather-sealed body of the RZ18, you can use this camera with more confidence under conditions where there is risk of exposure to water and dust compared to the ZS40.
LCD Screen Size and Features
Panasonic ZS40 and Pentax RZ18's LCD screens have the same diagonal size of 3.00 inches.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.