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 ZR3 and Pentax WG-3 GPS side-by-side from the front, back and top in their relative dimensions. Panasonic ZR3 has external dimensions of 98 x 55 x 26 mm (3.86 x 2.17 x 1.02″) and weighs 159 g (0.35 lb / 5.61 oz) (including batteries). Pentax WG-3 GPS has external dimensions of 125 x 64 x 33 mm (4.9 x 2.5 x 1.3″) and weighs 238 g (0.52 lb / 8.40 oz) (including batteries).
Below you can see the front-view size comparison of the Panasonic ZR3 and the Pentax WG-3 GPS. Panasonic ZR3 is clearly the smaller of the two cameras. Its body is 27mm narrower, 9mm shorter and 7mm thinner than Pentax WG-3 GPS.
Here is the back view size comparison of the Panasonic ZR3 and Pentax WG-3 GPS.
Now lets look at the top view comparison of Panasonic ZR3 and Pentax WG-3 GPS.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Panasonic ZR3 is significantly lighter (79g ) than the Pentax WG-3 GPS which may become a big advantage especially on long walking trips.
Weather Sealing
Thanks to the weather-sealed body of the WG-3 GPS, you can use this camera with more confidence under conditions where there is risk of exposure to water and dust compared to the ZR3.
LCD Screen Size and Features
Pentax WG-3 GPS's 3.00" LCD screen is slightly larger than Panasonic ZR3's 2.7 screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.