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 YI M1 and Sony A9 side-by-side from the front, back and top in their relative dimensions. YI M1 has external dimensions of 114 x 64 x 34 mm (4.49 x 2.52 x 1.34″) and weighs 350 (including batteries). Sony A9 has external dimensions of 127 x 96 x 63 mm (5 x 3.78 x 2.48″) and weighs 673 g (1.48 lb / 23.74 oz) (including batteries).
Below you can see the front-view size comparison of the YI M1 and the Sony A9. YI M1 is clearly the smaller of the two cameras. Its body is 13mm narrower, 32mm shorter and 29mm thinner than Sony A9.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
YI M1 is 673g lighter than the Sony A9 but we don't think this will make a significant difference.
Also keep in mind that body weight is not the only deciding factor when comparing two interchangeable camera bodies, you also have to take into account the lenses that you will be using with these bodies. Since Sony A9 has a Full frame sensor and YI M1 has a smaller Four Thirds sensor, YI M1's lenses for a similar focal length and aperture will generally be lighter and smaller than the Sony A9 lenses.
Weather Sealing
Thanks to the weather-sealed body of the A9, you can use this camera with more confidence under conditions where there is risk of exposure to water and dust compared to the M1.
LCD Screen Size and Features
YI M1 and Sony A9's LCD screens have the same diagonal size of 3.00 inches.
On the other hand, Sony A9 features a
Tilting screen where you can change the angle of the screen to make it easier to shoot from waist or over-the-head levels whereas the YI M1 has a fixed type screen which provides less flexibility in shooting positions compared to A9.