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 Nikon P100 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). Nikon P100 has external dimensions of 114 x 83 x 99 mm (4.49 x 3.27 x 3.9″) and weighs 481 g (1.06 lb / 16.97 oz) (including batteries).
Below you can see the front view size comparison of Panasonic ZS3 and Nikon P100. Panasonic ZS3 is clearly the smaller of the two cameras. Its body is 11mm narrower, 23mm shorter and 66mm thinner than Nikon P100.
Here is the back view size comparison of Panasonic ZS3 and Nikon P100.
Now lets look at the top view comparison of Panasonic ZS3 and Nikon P100.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Panasonic ZS3 is significantly lighter (252g ) than the Nikon P100 which may become a big advantage especially on long walking trips.
Unfortunately neither Panasonic Lumix DMC-ZS3 (Lumix DMC-TZ7) nor Nikon Coolpix P100 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 Top Bridge Cameras with Weather Sealing
LCD Screen Size and Features
Panasonic ZS3 and Nikon P100's LCD screens has the same diagonal size of 3".
On the other hand, Nikon P100 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 Panasonic ZS3 has a fixed type screen which provides less flexibility in shooting positions compared to P100.