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 Sony A100 and Leica V-Lux 4 side-by-side from the front, back and top in their relative dimensions. Sony A100 has external dimensions of 133 x 95 x 71 mm (5.24 x 3.74 x 2.8″) and weighs 638 g (1.41 lb / 22.50 oz) (including batteries). Leica V-Lux 4 has external dimensions of 125 x 87 x 110 mm (4.92 x 3.43 x 4.33″) and weighs 588 g (1.30 lb / 20.74 oz) (including batteries).
Below you can see the front view size comparison of Sony A100 and Leica V-Lux 4. Leica V-Lux 4 is 8mm narrower and 8mm shorter than Sony A100 but it is also 39mm thicker. As you can tell, actually this is not a fair size comparison since Leica V-Lux 4 has a built-in lens but Sony A100 doesn't. Once you put a lens on A100, its thickness will increase significantly.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Leica V-Lux 4 is 50g lighter than the Sony A100 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 A100, the total kit will weigh much higher.
Unfortunately neither Sony Alpha DSLR-A100 nor Leica V-Lux 4 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 DSLR Cameras with Weather Sealing Top Bridge Cameras with Weather Sealing
LCD Screen Size and Features
Leica V-Lux 4's 3.00" LCD screen is slightly larger than Sony A100's 2.5" screen.
Moreover, Leica V-Lux 4 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. On the other hand, Sony A100 has a fixed type screen which provides almost no flexibility in shooting positions compared to V-Lux 4.