OM SYSTEM Olympus OM-3 Silver Micro Four Thirds vs Sony a7III Full Frame Mirrorless Camera with FE 28-
Updated August 2026 — OM SYSTEM Olympus OM-3 Silver Micro Four Thirds wins on price, Sony a7III Full Frame Mirrorless Camera with FE 28- wins on battery and image quality.
The OM SYSTEM Olympus OM-3 offers creative features and a durable design at a lower price, while the Sony a7III excels in image quality and performance.
Why OM SYSTEM Olympus OM-3 Silver Micro Four Thirds is better
Price
OM-3 is $199 cheaper than a7III
Build Quality
OM-3 has IP53 weather sealing
Creative Features
OM-3 offers unique computational photography options
Why Sony a7III Full Frame Mirrorless Camera with FE 28- is better
Image Quality
a7III has a higher 24.2 MP sensor
Battery Life
a7III lasts up to 710 shots
Autofocus
a7III has superior autofocus coverage
Overall score
Specifications
| Spec | OM SYSTEM Olympus OM-3 Silver Micro Four Thirds | Sony a7III Full Frame Mirrorless Camera with FE 28- |
|---|---|---|
| Sensor MP | 20 MP | 24.2 MP |
| Dynamic Range | N/A | 15 stops |
| Viewfinder | 2.36m-dot OLED | 3-inch LCD |
| Shooting Speed | N/A | 10 fps |
| Weather Sealing | IP53 | No |
Dimension comparison
Design and Build Quality
The OM SYSTEM Olympus OM-3 features a vintage-styled, premium metal body that exudes durability and aesthetic appeal. In contrast, the Sony a7III offers a robust design aimed at professional use, but it doesn't have the same vintage charm. While both cameras are well-built, the OM-3's IP53 rating makes it dustproof, splashproof, and freezeproof, which is a significant advantage for outdoor photographers. The pricing reflects this quality, with the OM-3 priced at $1,699.99, making it about 10% less expensive than the Sony a7III at $1,898.00.
Image Quality and Sensor Performance
When it comes to image quality, the Sony a7III boasts a 24.2 MP BSI full-frame image sensor, providing excellent low-light performance and dynamic range. In comparison, the OM SYSTEM Olympus OM-3 uses a 20 MP stacked BSI Live MOS sensor. While both sensors are advanced, the a7III offers a higher resolution, which can be crucial for large prints or cropping in post-production. Users will appreciate the 15-stop dynamic range of the a7III, which enhances its versatility for various shooting conditions, making it ideal for professionals.
Features and Capabilities
The OM SYSTEM Olympus OM-3 includes a range of computational photography features, such as Live ND and High Res Shot, making it an excellent choice for creative photographers. On the other hand, the Sony a7III is geared towards performance with its up to 10fps shooting speed and impressive autofocus system that covers 93% of the frame. While the OM-3 excels in creative control with its S&Q Mode for slow and quick motion video, the a7III focuses on delivering fast, high-quality images, which may be more appealing for action and event photographers.
Viewfinder and Display
Both cameras incorporate advanced viewfinder technology, but they cater to different preferences. The OM SYSTEM Olympus OM-3 has a 2.36m-dot OLED electronic viewfinder, which offers a clear, vibrant image for composing shots. Meanwhile, the Sony a7III features a slightly lower resolution viewfinder but compensates with its 3-inch LCD monitor that has excellent visibility in various lighting conditions. The a7III's viewfinder setup is particularly useful for those who prefer shooting through the lens with real-time feedback.
Battery Life
Battery life is a crucial consideration for photographers, especially when shooting for extended periods. The Sony a7III excels here, offering approximately 610 shots with the viewfinder and around 710 shots using the LCD monitor. In contrast, the OM SYSTEM Olympus OM-3 does not provide specific battery life stats in the available data. For photographers who rely on long shooting sessions without the opportunity to recharge, the a7III's battery performance could be a deciding factor.
Lens Compatibility
The OM SYSTEM Olympus OM-3 is built on the Micro Four Thirds system, providing access to a wide variety of lenses designed for compact systems. This versatility is appealing for photographers looking to expand their lens collection. Conversely, the Sony a7III is compatible with Sony E mount lenses, which opens up a vast array of options for full-frame photography. Both systems offer excellent lens choices, but users should consider their existing investments in lenses when making a decision.
Price and Value
The OM SYSTEM Olympus OM-3 is currently priced at $1,699.99, making it about 10% cheaper than the Sony a7III, which retails at $1,898.00. This price difference may appeal to budget-conscious photographers seeking quality in a compact form. However, the a7III's advanced features, higher resolution, and robust performance may justify the extra cost for professional users. The OM-3, while less expensive, offers unique features that may attract enthusiasts looking for creative photography options.
Which should you buy?
Choosing between the OM SYSTEM Olympus OM-3 and the Sony a7III ultimately depends on your specific needs as a photographer. If you value a durable, weather-sealed body with creative features for unique shots, the OM-3 is a fantastic choice at a lower price point. However, if you prioritize image quality, battery life, and performance, the Sony a7III stands out as a premium option that caters to professional standards. Assess your photographic style and requirements to make an informed decision that best suits your needs.

