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 ZS3 and Casio EX-Z800 side-by-side from the front, back and top in their relative dimensions. Panasonic ZS3 has external dimensions of 103 x 60 x 33 mm (4.06 x 2.36 x 1.3″) and weighs 229 g (0.50 lb / 8.08 oz) (including batteries). Casio EX-Z800 has external dimensions of 91 x 52 x 20 mm (3.58 x 2.05 x 0.79″) and weighs 124 g (0.27 lb / 4.37 oz) (including batteries).
Below you can see the front-view size comparison of the Panasonic ZS3 and the Casio EX-Z800. Casio EX-Z800 is clearly the smaller of the two cameras. Its body is 12mm narrower, 8mm shorter and 13mm thinner than Panasonic ZS3.
Here is the back view size comparison of the Panasonic ZS3 and Casio EX-Z800.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Casio EX-Z800 is significantly lighter (105g ) than the Panasonic ZS3 which may become a big advantage especially on long walking trips.
Weather Sealing
Unfortunately neither the Panasonic Lumix DMC-ZS3 (Lumix DMC-TZ7) nor Casio Exilim EX-Z800 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
Panasonic ZS3's 3.00" LCD screen is slightly larger than Casio EX-Z800's 2.7 screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.