Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Panasonic S 24-70mm F2.8 is the longer of the two lenses at 140mm. The Leica SL 24-70mm F2.8 with a length of 123mm is 17mm shorter. Besides being longer, the Panasonic S 24-70mm F2.8 also has a larger diameter of 91mm compared to Leica SL 24-70mm F2.8's 88mm diameter.
Below you can find the scaled side by side image of Leica SL 24-70mm F2.8 and Panasonic S 24-70mm F2.8 to get a better idea of how their size compare in real life.
Weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Leica SL 24-70mm F2.8 weighs 856g, which means it is 79g (8%) lighter than the Panasonic S 24-70mm F2.8 which has a weight of 935g.
Both Leica SL 24-70mm F2.8 has the Leica L lens mount whereas the Panasonic S 24-70mm F2.8 has the Leica SL lens mount. Some of the latest released cameras that are compatible with these mounts are Sigma fp L, Leica SL2-S and Panasonic S5 for the Leica L Mount and Sigma fp L, Leica SL2-S and Panasonic S5 for the Leica SL Mount.
Both lenses have the same focal range of 24-70mm and the fastest aperture of F2.8.