Size and weight is a big decision factor when you are trying to find the ideal camera for your needs.
In this section, We are going to illustrate Sony RX100 III and Sony HX90V side-by-side from the front, back and top in their relative dimensions. Sony RX100 III has external dimensions of 102 x 58 x 41 mm (4.02 x 2.28 x 1.61″) and weighs 290 g (0.64 lb / 10.23 oz) (including batteries). Sony HX90V has external dimensions of 102 x 58 x 36 mm (4.02 x 2.28 x 1.42″) and weighs 245 g (0.54 lb / 8.64 oz) (including batteries).
Below you can see the front view size comparison of Sony RX100 III and Sony HX90V. Sony RX100 III has the same height and width with Sony HX90V. On the other hand, with a thickness of 41mm, it is 5mm thicker.
Here is the back view size comparison of Sony RX100 III and Sony HX90V.
Now lets look at the top view comparison of Sony RX100 III and Sony HX90V.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Sony HX90V is significantly lighter (45g ) than the Sony RX100 III which may become a big advantage especially on long walking trips.
Unfortunately neither Sony Cyber-shot DSC-RX100 III nor Sony Cyber-shot DSC-HX90V provides any type of weather sealing in their body, 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
Sony RX100 III and Sony HX90V's LCD screens has the same diagonal size of 3.00".
Both cameras feature Tilting screens
where you can change the angle of the screen to make it easier to shoot from waist or over the head levels.