Size and weight is a big decision factor when you are trying to find the ideal camera for your needs.
In this section, We are going to illustrate Panasonic ZS3 and Olympus SZ-12 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). Olympus SZ-12 has external dimensions of 106 x 69 x 40 mm (4.17 x 2.72 x 1.57″) and weighs 226 g (0.50 lb / 7.97 oz) (including batteries).
Below you can see the front view size comparison of Panasonic ZS3 and Olympus SZ-12. Panasonic ZS3 is clearly the smaller of the two cameras. Its body is 3mm narrower, 9mm shorter and 7mm thinner than Olympus SZ-12.
Now lets look at the top view comparison of Panasonic ZS3 and Olympus SZ-12.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Olympus SZ-12 is 3g lighter than the Panasonic ZS3 but we don't think this will make a significant difference.
Unfortunately neither Panasonic Lumix DMC-ZS3 (Lumix DMC-TZ7) nor Olympus SZ-12 provides any type of weather sealing in their body, 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 and Olympus SZ-12's LCD screens has the same diagonal size of 3".
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.