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 Olympus SP-820UZ and Pentax XG-1 side-by-side from the front, back and top in their relative dimensions. Olympus SP-820UZ has external dimensions of and weighs 485 g (1.07 lb / 17.11 oz) (including batteries). Pentax XG-1 has external dimensions of 119 x 89 x 98 mm (4.69 x 3.5 x 3.84″) and weighs 567 g (1.25 lb / 20.00 oz) (including batteries).
Below you can see the front-view size comparison of the Olympus SP-820UZ and the Pentax XG-1. Olympus SP-820UZ is clearly the smaller of the two cameras. Its body is 2mm narrower, 11mm shorter and 5mm thinner than Pentax XG-1.
Now lets look at the top view comparison of Olympus SP-820UZ and Pentax XG-1.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Olympus SP-820UZ is significantly lighter (82g ) than the Pentax XG-1 which may become a big advantage especially on long walking trips.
Weather Sealing
Unfortunately neither the Olympus Stylus SP-820UZ nor Pentax XG-1 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 Bridge Cameras with Weather Sealing
LCD Screen Size and Features
Olympus SP-820UZ and Pentax XG-1's LCD screens have the same diagonal size of 3.00 inches.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.