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 170 IS and Canon ELPH 340 HS side-by-side from the front, back and top in their relative dimensions. Canon 170 IS has external dimensions of 100 x 58 x 23 mm (3.94 x 2.28 x 0.91″) and weighs 141 g (0.31 lb / 4.97 oz) (including batteries). Canon ELPH 340 HS has external dimensions of 100 x 58 x 22 mm (3.93 x 2.27 x 0.88″) and weighs 147 g (0.32 lb / 5.19 oz) (including batteries).
Below you can see the front-view size comparison of the Canon 170 IS and the Canon ELPH 340 HS. Canon 170 IS has the same height and width with Canon ELPH 340 HS. On the other hand, with a thickness of 23mm, it is 1mm thicker.
Here is the back view size comparison of the Canon 170 IS and Canon ELPH 340 HS.
Now lets look at the top view comparison of Canon 170 IS and Canon ELPH 340 HS.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Canon 170 IS is 6g lighter than the Canon ELPH 340 HS but we don't think this will make a significant difference.
Weather Sealing
Unfortunately neither the Canon PowerShot ELPH 170 IS (IXUS 170) nor Canon PowerShot ELPH 340 HS (IXUS 265 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
LCD Screen Size and Features
Canon ELPH 340 HS's 3.00" LCD screen is slightly larger than Canon 170 IS's 2.7 screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.