Olympus OM System OM-1 vs Sony A7 IV: A Deep Dive into Pro Mirrorless Contenders

When it comes to choosing a pro-grade mirrorless camera, the Olympus OM System OM-1 and the Sony Alpha A7 IV are two standout options that continue to generate passionate discussion among advanced enthusiasts and professionals alike. Both cameras bring innovative technology and powerful capabilities to the table, but they represent distinctly different philosophies. As seasoned reviewers who have tested thousands of cameras over 15+ years, we’ll guide you through a detailed comparison to help you find the best fit for your creative journey.

We’ll evaluate image quality, autofocus, build, usability, video performance, and more - across diverse photography types like portrait, landscape, wildlife, and video content creation. Our analysis blends technical insights with hands-on experience to give you actionable information beyond spec sheets.

Let’s unpack these two exceptional cameras to understand their strengths and potential trade-offs.

Feel It in Your Hands: Size, Ergonomics, and Controls

First impressions count, especially when you’ll be carrying a camera for hours. Here, build quality and ergonomics often shape your daily experience.

Olympus OM System OM-1: The OM-1 stands out with its compact and lightweight design - roughly 100g lighter than the Sony. Its muscular, SLR-style grip is surprisingly ergonomic for a smaller body. The fully articulated 3” touchscreen is highly responsive, ideal for vlogging or shooting at tricky angles. The even higher-resolution electronic viewfinder (5670K dots) offers detailed framing clarity, particularly useful in bright outdoor conditions.

Sony A7 IV: While slightly larger and heavier, the A7 IV’s dimensions prioritize a robust grip and balanced feel, especially with larger lenses. Its full-frame form factor naturally requires more heft. The fully articulated screen is slightly lower resolution but still versatile for video and photography. Sony’s viewfinder, while excellent, doesn’t quite match Olympus in resolution but still offers bright and lag-free performance.

In terms of control layout, Olympus doubles down on simplicity and logical button placement without overwhelming users - great for photographers who want quick access without fuss. Sony offers a generous array of dials and customizable buttons, appealing to power users who demand granular control.

Sensor Technology and Image Quality: Different Roads to Excellence

At the core of any camera’s image-producing power is the sensor. The OM-1 and A7 IV use distinct sensor technologies that define their strengths and limitations.

The large, 33MP full-frame sensor on the Sony offers a clear advantage for resolution-dependent tasks like landscape and commercial photography. Its high pixel count combined with excellent native ISO sensitivity grants remarkable dynamic range and low noise performance in demanding light.

Conversely, the Olympus OM-1 showcases a smaller Four Thirds sensor but adopts cutting-edge stacked BSI Live MOS architecture. This design enables faster readout speeds, crucial for reducing rolling shutter and enabling fast autofocus, albeit with a resolution capped at 20MP. The sensor’s lack of an optical low-pass filter helps maximize sharpness, but some may prefer the Sony’s more forgiving AA filter to reduce moiré in detailed scenes.

In practice: The Sony excels in scenarios requiring high-resolution files and wide tonal latitude - like studio product or expansive landscape work. The OM-1’s sensor shines in speed-focused genres, offering more agility and fast, reliable AF performance.

Autofocus Brilliance and Burst Performance

Both cameras promise advanced autofocus (AF) systems, but their approaches and effectiveness differ.

The OM-1 impresses with its extraordinarily dense AF point array and advanced AI-assisted subject recognition. The 1053 phase-detect points cover nearly the entire frame, enabling aggressive tracking of fast-moving subjects like birds or athletes. The silent electronic shutter can reach ultra-fast 1/32000 sec speeds, allowing you to shoot wide-open in bright light without ND filters.

Sony’s A7 IV features a slightly lower count of AF points, but its AF algorithms are battle-tested and highly reliable, known for quick and accurate eye detection in both humans and animals. The 10 fps burst rate matches the Olympus, but Sony's autofocus excels in continuous tracking, especially in low-light sports scenarios.

Our real-world tests found:

• OM-1: Superb subject tracking with minimal focus hunting; best-in-class for wildlife and macro.
• A7 IV: Excellent autofocus speed and precision, with outperforming performance in dim environments and complex scenes.

Handling and User Interface: Making Your Workflow Smoother

Both cameras feature fully articulated touchscreens and electronic viewfinders to aid composition and review.

Olympus raises the bar with a slightly higher-resolution touchscreen that supports intuitive touch-to-focus and customizable menus. The physical buttons and dials on OM-1 have been thoughtfully placed for one-handed operation, making it easier to adjust settings on the fly.

Sony’s larger body accommodates ergonomic grips and more extensive control customization, appealing to photographers who rely heavily on manual adjustments. The UI is layered but logically organized, though some newcomers may encounter a slight learning curve.

Both support dual storage media slots, but there’s a notable difference:

• OM-1: Dual SD UHS-II slots (first slot faster).
• A7 IV: Dual SD and CFexpress Type A slots, giving more speed and reliability for burst shooting and 4K video capture.

Battery life slightly favors Sony’s generous 600-shot rating versus 520 for Olympus, though real-world usage varies with settings and temperature.

Lens Ecosystem and Compatibility: The Power of Glass

Your choice in lenses can dramatically influence creative possibilities. Here’s how both systems stack up:

While the OM-1’s Micro Four Thirds mount has fewer native primes than Sony’s E-mount, it offers a compact, affordable lens lineup - especially excellent for macro and telephoto. The smaller sensor also makes long lenses more affordable and lighter for wildlife photography.

Sony’s E-mount supports an expansive, mature lens catalog with numerous professional-grade fast primes and zooms suitable for portraits, landscapes, weddings, and everything in between. The full-frame sensor benefits from these optics’ full angle-of-view and optical quality, albeit with more bulk in total kit weight for telephoto or wide-angle setups.

Your choice depends heavily on your lens priorities. Olympus is undeniably the lightweight, fast-lens option for rapid action, while Sony favors ultimate resolution, optical variety, and build quality.

Versatility in Photography Genres: Match Your Camera to Your Vision

Let’s break down how each camera excels across popular photography disciplines:

Portrait Photography

• OM System OM-1:
  • Excellent eye and animal eye AF for sharp focus on faces.
  • Artistically pleasing bokeh achievable with select lenses despite smaller sensor.
  • High ISO performance adequate but noise becomes apparent above ISO 6400.
• Sony A7 IV:
  • Superior skin tone rendition thanks to larger sensor and 33MP resolution.
  • The AA filter reduces moiré increasing smoothness in portraits.
  • Exceptional autofocus eye detection, works well in low light.

Landscape Photography

• OM System OM-1:
  • Solid dynamic range but limited compared to full frame.
  • Weather sealing and compact size great for rough terrain and travel.
  • 20MP resolution may limit large print sizes.
• Sony A7 IV:
  • Much larger sensor area delivers stunning dynamic range and detail.
  • Higher resolution files better for cropping and huge prints.
  • Excellent weather sealing and build for rugged outdoor use.

Wildlife Photography

• OM System OM-1:
  • Wins with extremely fast AF, high frame rate, and silent electronic shutter.
  • 2.1x crop factor extends telephoto reach affordably.
  • Lightweight system reduces fatigue in long field sessions.
• Sony A7 IV:
  • Good AF tracking but heavier lenses increase gear weight.
  • Full-frame sensor provides excellent image quality at distance.
  • Larger battery life critical for long shoots.

Sports Photography

• Both cameras offer a 10 fps burst with reliable AF tracking, but Sony typically edges Olympus in challenging light.
• Olympus OM-1’s silent shutter avoids distracting noise in indoor events.
• Sony’s superior high ISO and larger buffer support longer continuous shooting.

Street Photography

• OM-1 shines due to discreet size, light weight, and quick response.
• Sony’s larger body is less stealthy but offers superior low-light handling.
• Both have articulating screens for candid shooting angles.

Macro Photography

• Olympus offers focus bracketing and stacking features native in-camera.
• Lightweight OM lenses optimize field macro shooting.
• Sony relies on third-party lenses and lacks built-in stacking.

Night/Astro Photography

• Sony A7 IV’s full-frame sensor excels in high ISO performance and noise control.
• Olympus provides long exposure capabilities but faces more noise at extreme ISOs.
• Both support timelapse but Sony’s larger buffer is an advantage.

Video Capabilities

Sony takes the lead with superior codec options (XAVC S and S-I) allowing higher bitrates for professional video production. The A7 IV also boasts advanced autofocus during video recording, granting seamless face and eye tracking. Olympus supports excellent in-body stabilization, but video-centric features are comparatively limited.

Travel Photography

• OM-1’s small footprint and robust weather resistance make it a top pick for travel enthusiasts wanting versatility without bulk.
• Sony’s longer battery life, broader lens range, and higher image quality appeal more to professionals needing all-in-one capability.

Professional Workflows

• Both cameras support uncompressed and compressed RAW formats with deep color profiles.
• Sony’s CFexpress Type A slot enables faster offloading critical in high-volume workflows.
• Olympus delivers reliable tethering over USB, but Sony benefits from longer-established software compatibility.

Connectivity, Storage, and Power: Staying Connected and Powered All Day

Connectivity and battery performance are vital for any serious shooter.

Sony gains a slight advantage in battery life and storage flexibility with the CFexpress slot allowing ultra-fast data writing, ideally suited for burst and 4K video. Olympus is competitive with dual SD slots and fast USB transfer, although lacking NFC may hamper instant sharing in some setups.

Real-World Image Samples and Performance Scores

Seeing is believing. Below, you’ll find representative sample images captured in various conditions, illustrating each camera’s strengths and artistic potential:

OM System OM 1 front OM System OM 1 screen back Sony A7 IV front Sony A7 IV screen back

Our lab and field testing consolidate into overall and genre-specific performance ratings:

• Olympus OM-1 scores highest in wildlife, sports, and macro.
• Sony A7 IV leads in landscape, portrait, and video disciplines.

Summing It Up: Which Should You Choose?

Both the OM System OM-1 and Sony A7 IV are formidable tools tailored for distinct user profiles.

Choose Olympus OM System OM-1 if:

• You prioritize lightweight, highly portable gear.
• Wildlife, sports, macro, and fast-action shooting are your focus.
• You want outstanding in-camera stabilization and rapid autofocus with silent shooting.
• Your lens strategy favors compact telephotos and versatility.
• You appreciate a high-res EVF and an intuitive control layout.

Choose Sony A7 IV if:

• Image resolution and dynamic range are paramount, especially for landscapes or portraiture.
• You require a mature lens ecosystem with professional-grade optics.
• Video production with high bitrate codecs and extensive autofocus video features is important.
• You prefer slightly longer battery life and expanded storage options.
• You want the performance benefits of a full-frame sensor.

Final Thoughts

Your perfect camera depends as much on your shooting style and priorities as on technical specifications. The Olympus OM System OM-1 redefines what a small mirrorless can do - pushing speed, precision, and portability to new heights. Meanwhile, Sony’s A7 IV remains the all-round powerhouse providing world-class image quality, flexibility, and professional features.

We recommend trying both hands-on if possible. Handling these cameras side by side will reveal personal preferences in ergonomics, UI, and how each system’s lenses feel on your hands.

Consider lenses and accessories alongside bodies to build your ideal kit. Whether it’s compact agility with the OM-1 or full-frame versatility with the A7 IV, both cameras empower you to capture stunning images and master your artistic vision.

Explore further, get shooting, and let these fantastic cameras help you tell your story with clarity and creativity.

Ready to expand your photographic horizons? Check out official Olympus and Sony websites, local photography retailers, or rental services to get familiar with both systems before deciding. The journey to better images starts with the right tool in your hands.