Olympus TG-850 iHS vs Sony A7R III: A Deep Dive Into Two Cameras from Different Worlds

When you have two cameras as distinctly different as the Olympus Stylus Tough TG-850 iHS and the Sony Alpha A7R III side-by-side, the temptation is to either dismiss them as apples and oranges or obsessively pit features against features like a technical boxing match. But I’m here to tell you - there’s plenty to learn by juxtaposing these titans from vastly different categories: a rugged compact waterproof point-and-shoot versus a flagship professional full-frame mirrorless powerhouse.

Having personally tested thousands of cameras across genres - from the wilds of wildlife photography to the quiet precision of studio portraiture - I'm excited to walk you through these cameras with practical insights. We’ll unpack their real-world performance, technical prowess, handling quirks, and ultimately who each camera serves best.

So buckle up for a 2500-word journey, peppered with first-hand impressions, detailed technical comparisons, and a sprinkle of good-natured skepticism about marketing claims. Let’s get started.

Size, Build, and Handling: Compact Rugged vs SLR-Style Mirrorless

At first glance, the Olympus TG-850 iHS and Sony A7R III couldn’t be more different physically. The TG-850 is designed for adventure - completely waterproof, shockproof, freezeproof, and crushproof. It’s a compact that fits in your jacket pocket, weighed down by a mere 218 grams, sporting dimensions of 110x64x28 mm. The Sony A7R III, by contrast, is an SLR-style mirrorless camera, built for serious work in full-frame format, and it weighs almost three times as much at 657 grams, stretching 127x96x74 mm.

Here’s a visual side-by-side:

Handling-wise, the Olympus TG-850 iHS feels like a Swiss Army knife designed for dirt, water, and rough handling. Its waterproofing (up to 15m depth) and shock resistance (drop-proof to 2.1m) mean you can take it hiking, skiing, or snorkeling without second thoughts. The build is plastic-heavy but robust, with sealed controls and rubberized grips.

The A7R III, however, is built like a tank with a magnesium alloy body, weather sealing around buttons and compartments - but it’s emphatically not waterproof. This camera demands care but rewards with professional ergonomics: a deep grip, logical button layout, and dual SD card slots that compliment professional workflows.

The top view further highlights the difference in control philosophy:

The Sony’s button dials, joystick, and customizable buttons put manual control at your fingertips. The Olympus relies on simpler controls - few buttons, no manual exposure modes, and no mechanical dials - consistent with its point-and-shoot positioning.

If you’re prioritizing portability and ruggedness with easy operation, TG-850 wins the handling battle hands down. For photographers who crave tactile control and confidence-in-hand for demanding shoots, the A7R III’s heft and button layout shine.

Sensor Size and Image Quality: Micro Compact vs Full Frame Powerhouse

This is where the rubber meets the road - or the pixel hits the sensor. The two cameras couldn’t be more opposite in sensor design and technology.

The Olympus TG-850 iHS sports a small 1/2.3" (6.17 x 4.55 mm) BSI-CMOS sensor with a resolution of 16 megapixels. It’s a typical compact sensor size, optimized for small-sensor point-and-shoot cameras. This sensor size limits dynamic range and low-light performance but enables the camera to maintain a slim profile and robust waterproof construction.

On the flip side, the Sony A7R III uses a vast 35.9 x 24 mm full-frame BSI-CMOS sensor boasting 42 megapixels – 2.6 times the resolution pixel-wise and more than 30 times the sensor area. The sensor’s lack of an anti-aliasing filter means image sharpness is pushed to the max, though at the expense of a bit more moiré potential in certain textures.

To put it into perspective: the Sony has an DxO Mark overall score around 100 with outstanding color depth (26 bits), dynamic range of 14.7 EV, and exceptional low-light ISO capability (native max ISO 32,000, expandable to ISO 102,400). The Olympus sensor, while unranked by DxO, is typical for compact rugged cameras, offering reliable daylight images but struggling with noise and limited tonal range in shadow and highlight.

These technical differences translate directly into image quality. The Sony’s full-frame sensor captures photos with granular detail, luscious gradations in tones, and excellent high ISO performance - key for professional portraiture, landscape, and low-light genres.

The Olympus, meanwhile, shines when you hand it off to casual shooters seeking convenience and durability rather than critical image fidelity.

Viewing and Interface: LCD Screens and Viewfinders

Neither camera offers an optical viewfinder, but their LCD screen implementations are quite different.

The Olympus TG-850 iHS features a 3” tilting TFT LCD with 460k dots resolution. The screen tilts upward or downward for awkward angles, which is handy for underwater shooting or low-to-the-ground macro snaps. However, the modest screen resolution and lack of touchscreen limited my control flexibility and image review comfort.

The Sony A7R III sports a 3" tilting LCD with a sharply higher 1440k dots resolution and crucially supports touchscreen for focus point selection and menu navigation - hugely helpful when working quickly during shoots. Its electronic viewfinder (EVF) boasts a fantastic 3.69 million dots resolution, 100% coverage, and 0.78x magnification, offering clarity and framing precision nearly equal to optical viewfinders, but with the advantage of real-time exposure simulation and AF visualization.

If you often shoot outdoors in bright conditions, the Sony’s EVF alone is worth the price difference for its stable, daylight-visible framing. The Olympus relies entirely on its LCD, which can become hard to see in harsh light.

Autofocus and Speed: From Casual Snapshots to Pro Action

Getting the shot matters - and that’s where autofocus and burst performance come into play.

The Olympus TG-850 iHS does offer continuous autofocus, single autofocus, tracking, and face detection - impressive for a compact - though it uses contrast-detection AF with an unknown number of focus points (no phase-detection). It can shoot at 7 fps burst, which is surprisingly spry for a compact camera.

The Sony A7R III’s autofocus system is significantly more advanced, with 425 phase-detection points combined with contrast detection for highly accurate, fast AF coverage across 79% of the sensor. It supports real-time eye autofocus not only for humans but also for animals - a godsend for wildlife photography, pet portraits, or sports. Continuous shooting clocks at 10 fps with AF/AE tracking, a phenomenal feat for a 42MP camera.

I've tested the Sony's AF system in low light and fast-moving scenarios, and it delivers reliable, buttery-smooth focus acquisition almost invariably. The Olympus autofocus feels competent in bright environments but tends to hunt in dim light or with fast subjects.

Lens Ecosystem: Fixed Bridge vs Interchangeable Pro System

Here’s one area where the cameras reflect their cores distinctly.

The TG-850’s lens is fixed at 21-105mm equivalent focal length with an aperture range of f/3.5 to f/5.7 - modest but versatile for a compact. It does include optical image stabilization, which works well for handheld scenarios and even underwater. But the lack of interchangeable lenses and relatively slow aperture limits its creative flexibility, particularly in portrait and low-light situations.

The Sony A7R III uses the Sony E-mount, compatible with a vast ecosystem of more than 120 native lenses - including some stellar primes and professional zooms. This is an enormous advantage for photographers who want to swap lenses for portrait, macro, wildlife telephotos, or ultra-wide landscapes.

Having used the Sony with quality primes like the 85mm f/1.4 GM and the 24-70mm f/2.8 GM, I can vouch for the creative leap it provides over fixed-lens designs. It’s the kind of system you can build on for years.

Battery Life and Storage

Speaking of usability, the Olympus TG-850 bests expectations for a compact with an estimate of 330 shots per charge from a Lithium-ion LI-50B battery. Storage is handled via a single SD card slot or internal memory, which is modest but expected for its category.

Sony counters with a larger NP-FZ100 battery delivering an impressive 650 shots per charge - excellent for a professional mirrorless offering. It also boasts two SD card slots, including one supporting ultra-fast UHS-II cards. Dual slots not only mean more storage but peace of mind with automatic backup or overflow, an appreciated feature in professional settings.

Special Features: Video, Connectivity, and Extra Goodies

Video specs underscore the gap between amateur-friendly and professional ambitions.

Olympus TG-850 offers 1080p Full HD video at 60p using H.264 and Motion JPEG, a fair staple for casual video capture but far from cutting-edge. It omits microphone and headphone jacks, limiting audio control. Wireless connectivity exists but limited to Wi-Fi (no Bluetooth or NFC) for image transfer.

Sony A7R III supports UHD 4K video at 30p, plus Full HD up to 60p, encoded in MPEG-4, AVCHD, and the more efficient XAVC S format. It includes microphone and headphone ports for quality audio input and monitoring, vital for serious videographers. Bluetooth, Wi-Fi, and NFC are all built-in, enabling seamless remote control and fast image transfer.

If video is in your professional or creative scope, the Sony is a clear winner.

Real-World Performance across Photography Genres

This is the fun part - where theory meets fieldwork. I tested both cameras in various scenarios to see where their strengths truly lie.

Portrait Photography

Sony’s 42MP sensor plus excellent lens choices mean you get exquisite skin tones, smooth bokeh, and precise eye detection autofocus. The Olympus’s fixed f/3.5-5.7 lens can manage casual portraits but struggles with background blur and sharp focus separation.

Landscape Photography

The Sony’s huge dynamic range, high resolution, and weather-sealed body make it a landscape dream. Its full-frame sensor captures subtle tonal shifts in skies and shadows with breathtaking detail. Olympus can handle casual landscape shots but limited sensor size and dynamic range show in tricky lighting.

Wildlife Photography

Autofocus speed, tracking, and frame rates are crucial here. Sony’s 10 fps burst, 425 focus points, and animal eye AF system deliver professional-grade results for birds and mammals. Olympus’s 7 fps burst and contrast-detection AF lag behind.

Sports Photography

Similar to wildlife, Sony excels with fast and accurate tracking in variable light. Olympus can struggle in sports requiring high shutter speeds and selective AF presets.

Street Photography

The compactness and ruggedness of the Olympus make it ideal for spontaneous street shooting, no questions asked. Despite its size, Sony’s A7R III isn’t unwieldy but attracts more attention and demands care.

Macro Photography

Sony’s lens variety and sensor detail shine in macro. Olympus’s lack of focus stacking and fixed lens limit creativity, though good stabilization helps handheld macro shots.

Night and Astro Photography

Sony’s high ISO capability up to 102400 and long exposure capabilities, combined with no AA filter, make it highly capable for star trails and low-light scenes. Olympus’s small sensor and higher noise floor limit astrophotography success.

Video Capabilities

Sony’s 4K, microphone/headphone jacks, and professional codec support elevate it to semi-professional video workflows. Olympus is good for casual Full HD clips.

Travel Photography

If your travel photography demands risk-taking in rough environments, the Olympus TG-850 iHS is a trusty companion you don’t worry about dropping or submerging. Sony offers more image quality and lens versatility but is less splash-proof and bulkier.

Professional Work

Sony’s reliability, dual card slots, raw format support, and extensive customization make it ready for professional work. Olympus focuses on simplicity and durability over professional customization.

Summarizing Scores and Value

Let’s look at an objective snapshot of these cameras’ overall and specialized performance to wrap up the discussion.

Olympus TG 850 iHS front Olympus TG 850 iHS screen back Sony A7R III front Sony A7R III screen back

The sample images reflect Sony's superior detail and dynamic range versus Olympus’s versatile but modest output under casual use.

Sony A7R III clearly dominates in overall scores reflecting its technology and versatility, with Olympus paltry in comparison but excelling in rugged compact criteria.

Genre-specific scores further underscore the cameras’ emphasis: Olympus excels in travel, street, and waterproof ruggedness while Sony dominates in professional, landscape, wildlife, sports, and night photography.

Final Thoughts: Who Should Buy What?

Buy the Olympus Stylus Tough TG-850 iHS if:

• You want a highly durable, fully waterproof and shockproof camera to take snorkeling, hiking, or skiing without worry.
• You value portability, ease of use, and quick automated shooting over manual control or professional image quality.
• Your budget is tight (the TG-850 modestly retails around $250) and you want a grab-and-go camera that can handle casual family, vacation, or outdoor adventure snaps.
• You don’t need interchangeable lenses or advanced video features but want simple point-and-shoot reliability.

Buy the Sony Alpha A7R III if:

• You are a serious enthusiast or professional craving state-of-the-art full-frame image quality with 42MP resolution.
• Your photography spans demanding genres like portraiture, landscape, wildlife, sports, or astrophotography needing big sensor dynamic range, advanced auto-focus, and lens variety.
• You require pro-level video features including 4K capture and audio jacks.
• You work professionally and need robust build, dual card slots, high battery life, and workflow integration.
• Your budget accommodates the $2,800+ price and you value longevity in system investment.

In Conclusion

The Olympus TG-850 iHS and Sony A7R III aren’t simply cameras - you can think of them as statements of photographic philosophy. The TG-850 embraces simplicity and ruggedness with waterproof resilience ideal for adventurers who prioritize durability and convenience. The A7R III, meanwhile, pushes boundaries of optical quality, control, and versatility to meet the demands of professionals and dedicated enthusiasts striving for excellence in any lighting or genre.

My recommendation: The right choice depends on your priorities. Want a no-fuss lifesaver for outdoor escapades? TG-850 is your buddy. Need top-notch image quality and uncompromising performance? The A7R III is a professional treasure.

So, what’s your photographic journey? Whichever path you take, both cameras exemplify their categories well and can inspire you to create incredible images.

Happy shooting!

Note: The insights here come from extensive hands-on testing across environments, shooting scenarios, and workflows - and I hope they empower you to make a confident camera decision.