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 OM System OM-1 and Olympus E-M5 III side-by-side from the front, back and top in their relative dimensions. OM System OM-1 has external dimensions of 135 x 92 x 73 mm (5.3 x 3.6 x 2.87″) and weighs 599 g (1.32 lb / 21.13 oz) (including batteries). Olympus E-M5 III has external dimensions of 125 x 85 x 50 mm (4.92 x 3.35 x 1.97″) and weighs 414 g (0.91 lb / 14.60 oz) (including batteries).
Below you can see the front-view size comparison of the OM System OM-1 and the Olympus E-M5 III. Olympus E-M5 III is clearly the smaller of the two cameras. Its body is 10mm narrower, 7mm shorter and 23mm thinner than OM System OM-1.
Here is the back view size comparison of the OM System OM-1 and Olympus E-M5 III.
Now lets look at the top view comparison of OM System OM-1 and Olympus E-M5 III.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Olympus E-M5 III is significantly lighter (185g ) than the OM System OM-1 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 OM System OM-1 and Olympus E-M5 III have the same Micro Four Thirds lens mount and Four Thirds sized sensors, lenses will not be a differentiator on total size of the system.
Both the OM-1 and the E-M5 Mark III have weather sealings in their bodies, making them resistant to water and dust.
LCD Screen Size and Features
OM System OM-1 and Olympus E-M5 III's LCD screens have the same diagonal size of 3.00 inches.
Both cameras feature Fully Articulating screens
where you can change the angle of the screen to make it easier to shoot from waist or over-the-head levels. Fully articulating screens are also useful for taking Selfies and video.