OM System OM-3 vs Sony A7 III
Real-world comparison — specs, sensor size, autofocus, video, ownership reality. Adjust the workflow lens below to see how each body lands for travel, hybrid, wildlife, or studio use.
Visual
Estimated
Ranked
OM System OM-3
Micro 4/3 / 620g
Sony A7 III
Full-frame / 620g
Workflow lens
Sony A7 III is the stronger fit for travel and everyday carry.
Sony A7 III leads on video readiness by 26 points.
Sony A7 III leads on AF confidence by 14 points.
Sony A7 III leads on resale strength by 12 points.
Camera size studio
Relative body dimensions
Front, back and top views are drawn from external dimensions so the size relationship stays proportional.
View
Mode
OM System OM-3
Front view / 132 x 92mm
132 x 92 x 72mm
Sony A7 III
Front view / 132 x 92mm
132 x 92 x 72mm
Width
Height
Depth
Weight
External dimensions and carry delta
OM System OM-3 and Sony A7 III share the same external size profile in the current data model.
OM System OM-3
Sony A7 III
Class benchmarks
Sensor comparison
Sensor size to scale
×2 crop
×1 crop
Full-frame captures ~3.8× the sensor area of Micro 4/3, a real low-light and depth-of-field edge.
Decision matrix
Scores tuned for travel
Highlighted specs
Only specs that change the decision
Sensor
20MP stacked MFT
Sensor
24.2MP full-frame BSI
Weather sealing
IP53
Community comparison
Owner consensus · not specsCommunity comparison appears once owners vote on these products — 6 more votes across the pair will unlock it.
Where to buy
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OM System
OM System OM-3
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Sony
Sony A7 III
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Common questions
Answers from this comparison
Drawn from the products' specs and category facts — same logic the comparison engine uses for its verdict.
Is the OM System OM-3 better than the Sony A7 III?
Neither product is universally better — the right answer depends on what you shoot. Walk the use-case verdicts in the comparison studio above to see which body lines up with your specific work.
Which is better for travel — the OM System OM-3 or the Sony A7 III?
For travel, the combination of weight, weather sealing, and lens flexibility matters more than headline specs. The carry-envelope module in the comparison above breaks down the practical kit weight of each body with a normal lens attached.