Below you can see the front view size comparison of Panasonic S1R and Sony A7 III. Sony A7 III is clearly the smaller of the two cameras. Its body is 22mm narrower, 14mm shorter and 23mm thinner than Panasonic S1R.
Panasonic S1R vs Sony A7 III - Front View
Panasonic S1R vs Sony A7 III - Top View
The chart below depicts how two cameras compare with average dimensions of the cameras in their class.
Camera Size Comparison
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