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 Canon 1D MIII and Casio EX-S7 side-by-side from the front, back and top in their relative dimensions. Canon 1D MIII has external dimensions of 156 x 157 x 80 mm (6.14 x 6.18 x 3.15″) and weighs 1335 g (2.94 lb / 47.09 oz) (including batteries). Casio EX-S7 has external dimensions of 97 x 57 x 20 mm (3.82 x 2.24 x 0.79″) and weighs 121 g (0.27 lb / 4.27 oz) (including batteries).
Below you can see the front-view size comparison of the Canon 1D MIII and the Casio EX-S7. Casio EX-S7 is clearly the smaller of the two cameras. Its body is 59mm narrower, 100mm shorter and 60mm thinner than Canon 1D MIII. As you can tell, actually this is not a fair size comparison since Casio EX-S7 has a built-in lens but Canon 1D MIII doesn't. Once you put a lens on 1D MIII, its thickness will increase significantly.
Here is the back view size comparison of the Canon 1D MIII and Casio EX-S7.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Casio EX-S7 is significantly lighter (1214g ) than the Canon 1D MIII 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 1D MIII, the total kit will weigh much higher.
Weather Sealing
With its weather-sealed body, we believe that the 1D MIII has a big advantage over the EX-S7 which doesn't provide any kind of environmental sealing.
LCD Screen Size and Features
Canon 1D MIII's 3.00" LCD screen is slightly larger than Casio EX-S7's 2.7" screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.