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 Sigma fp and Sony A7 III side-by-side from the front, back and top in their relative dimensions. Sigma fp has external dimensions of 113 x 70 x 45 mm (4.45 x 2.76 x 1.77″) and weighs 422 g (0.93 lb / 14.89 oz) (including batteries). Sony A7 III has external dimensions of 127 x 96 x 74 mm (5 x 3.78 x 2.91″) and weighs 650 g (1.43 lb / 22.93 oz) (including batteries).
Below you can see the front-view size comparison of the Sigma fp and the Sony A7 III. Sigma fp is clearly the smaller of the two cameras. Its body is 14mm narrower, 26mm shorter and 29mm thinner than Sony A7 III.
Here is the back view size comparison of the Sigma fp and Sony A7 III.
Now lets look at the top view comparison of Sigma fp and Sony A7 III.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Sigma fp is significantly lighter (228g ) than the Sony A7 III which may become a big advantage especially on long walking trips.
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 both Sigma fp and Sony A7 III have the same Full frame sized sensor, their lenses for a similar focal length and aperture will be similar in size and weight.
Weather Sealing
Both the fp and the A7 III have weather sealings in their bodies, making them resistant to water and dust.
LCD Screen Size and Features
Sigma fp's 3.20" LCD screen is slightly larger than Sony A7 III's 3″ screen.