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 Nikon S4100 and Panasonic G1 side-by-side from the front, back and top in their relative dimensions. Nikon S4100 has external dimensions of 95 x 57 x 20 mm (3.74 x 2.24 x 0.79″) and weighs (including batteries). Panasonic G1 has external dimensions of 124 x 84 x 45 mm (4.88 x 3.31 x 1.77″) and weighs 360 g (0.79 lb / 12.70 oz) (including batteries).
Below you can see the front-view size comparison of the Nikon S4100 and the Panasonic G1. Nikon S4100 is clearly the smaller of the two cameras. Its body is 29mm narrower, 27mm shorter and 25mm thinner than Panasonic G1. As you can tell, actually this is not a fair size comparison since Nikon S4100 has a built-in lens but Panasonic G1 doesn't. Once you put a lens on G1, its thickness will increase significantly.
Here is the back view size comparison of the Nikon S4100 and Panasonic G1.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Nikon S4100 is 360g lighter than the Panasonic G1 but we don't think this will make a significant difference.
Again, this comparison may not be very useful in real life as we are comparing the weight of a camera with a built-in lens to the body-only weight of an interchangeable lens camera. Once you put a lens on G1, the total kit will weigh much higher.
Weather Sealing
Unfortunately neither the Nikon Coolpix S4100 nor Panasonic Lumix DMC-G1 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 Top Mirrorless Cameras with Weather Sealing
LCD Screen Size and Features
Nikon S4100 and Panasonic G1's LCD screens have the same diagonal size of 3.00 inches.
On the other hand, Panasonic G1 sports a
Fully Articulated screen which you can change the angle and position of the screen almost freely, making it possible to shoot from waist or over-the-head levels, and especially very useful for shooting selfies and video. Nikon S4100's LCD screen is a fixed type which provides almost no flexibility in shooting positions compared to G1.