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 Casio EX-ZR400 and Sony A580 side-by-side from the front, back and top in their relative dimensions. Casio EX-ZR400 has external dimensions of 105 x 59 x 29 mm (4.13 x 2.32 x 1.14″) and weighs 205 g (0.45 lb / 7.23 oz) (including batteries). Sony A580 has external dimensions of 137 x 104 x 84 mm (5.39 x 4.09 x 3.31″) and weighs 599 g (1.32 lb / 21.13 oz) (including batteries).
Below you can see the front-view size comparison of the Casio EX-ZR400 and the Sony A580. Casio EX-ZR400 is clearly the smaller of the two cameras. Its body is 32mm narrower, 45mm shorter and 55mm thinner than Sony A580. As you can tell, actually this is not a fair size comparison since Casio EX-ZR400 has a built-in lens but Sony A580 doesn't. Once you put a lens on A580, its thickness will increase significantly.
Here is the back view size comparison of the Casio EX-ZR400 and Sony A580.
Now lets look at the top view comparison of Casio EX-ZR400 and Sony A580.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Casio EX-ZR400 is significantly lighter (394g ) than the Sony A580 which may become a big advantage especially on long walking trips.
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 A580, the total kit will weigh much higher.
Weather Sealing
Unfortunately neither the Casio Exilim EX-ZR400 nor Sony Alpha DSLR-A580 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 DSLR Cameras with Weather Sealing
LCD Screen Size and Features
Casio EX-ZR400 and Sony A580's LCD screens have the same diagonal size of 3.00 inches.
On the other hand, Sony A580 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 Casio EX-ZR400 has a fixed type screen which provides less flexibility in shooting positions compared to A580.