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 Nikon S9100 and Nikon A side-by-side from the front, back and top in their relative dimensions. Nikon S9100 has external dimensions of 105 x 62 x 35 mm (4.13 x 2.44 x 1.38″) and weighs 214 g (0.47 lb / 7.55 oz) (including batteries). Nikon A has external dimensions of 111 x 64 x 40 mm (4.37 x 2.52 x 1.57″) and weighs 299 g (0.66 lb / 10.55 oz) (including batteries).
Below you can see the front view size comparison of Nikon S9100 and Nikon A. Nikon S9100 is clearly the smaller of the two cameras. Its body is 6mm narrower, 2mm shorter and 5mm thinner than Nikon A.
Comparison image of Nikon S9100 and Nikon A Size, Weight and External Dimensions - Front View
Here is the back view size comparison of Nikon S9100 and Nikon A.
Comparison image of Nikon S9100 and Nikon A Size and Weight - Back View
Now lets look at the top view comparison of Nikon S9100 and Nikon A.
Top View Comparison image of Nikon S9100 and Nikon A Size
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Nikon S9100 is significantly lighter (85g ) than the Nikon A which may become a big advantage especially on long walking trips.
Weather Sealing
Unfortunately neither Nikon Coolpix S9100 nor Nikon Coolpix A 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
Nikon S9100 and Nikon A'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.