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 SX150 IS and Canon SX40 HS side-by-side from the front, back and top in their relative dimensions. Canon SX150 IS has external dimensions of 113 x 73 x 46 mm (4.45 x 2.87 x 1.81″) and weighs 306 g (0.67 lb / 10.79 oz) (including batteries). Canon SX40 HS has external dimensions of 123 x 92 x 108 mm (4.84 x 3.62 x 4.25″) and weighs 600 g (1.32 lb / 21.16 oz) (including batteries).
Below you can see the front-view size comparison of the Canon SX150 IS and the Canon SX40 HS. Canon SX150 IS is clearly the smaller of the two cameras. Its body is 10mm narrower, 19mm shorter and 62mm thinner than Canon SX40 HS.
Now lets look at the top view comparison of Canon SX150 IS and Canon SX40 HS.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Canon SX150 IS is significantly lighter (294g ) than the Canon SX40 HS which may become a big advantage especially on long walking trips.
Weather Sealing
Unfortunately neither the Canon PowerShot SX150 IS nor Canon PowerShot SX40 HS 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
Canon SX150 IS's 3.00" LCD screen is slightly larger than Canon SX40 HS's 2.7 screen.