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 T8i and Sony A68 side-by-side from the front, back and top in their relative dimensions. Canon T8i has external dimensions of 131 x 103 x 76 mm (5.16 x 4.00 x 2.99″) and weighs 515 g (1.14 lb / 18.17 oz) (including batteries). Sony A68 has external dimensions of 143 x 104 x 81 mm (5.63 x 4.09 x 3.19″) and weighs 610 g (1.34 lb / 21.52 oz) (including batteries).
Below you can see the front-view size comparison of the Canon T8i and the Sony A68. Canon T8i is clearly the smaller of the two cameras. Its body is 12mm narrower, 1mm shorter and 5mm thinner than Sony A68.
Comparison image of the Canon T8i and the Sony A68 Size, Weight and External Dimensions - Front View
Here is the back view size comparison of the Canon T8i and Sony A68.
Comparison image of the Canon T8i and the Sony A68 Size and Weight - Back View
Now lets look at the top view comparison of Canon T8i and Sony A68.
Top View Comparison image of the Canon T8i and the Sony A68 Size
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Canon T8i is significantly lighter (95g ) than the Sony A68 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 Canon T8i and Sony A68 have the same APS-C sized sensor, their lenses for a similar focal length and aperture will be similar in size and weight.
Weather Sealing
Unfortunately neither the Canon EOS Rebel T8i (EOS 850D / EOS Kiss X10i) nor Sony SLT-A68 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 DSLR Cameras with Weather Sealing
LCD Screen Size and Features
Canon T8i's 3.00" LCD screen is slightly larger than Sony A68's 2.7 screen.