Olympus TG-870 vs. Sony A9: An Expert’s Deep-Dive on Two Cameras from Opposite Ends of the Spectrum

When comparing cameras as fundamentally different as the Olympus Stylus Tough TG-870 and the Sony Alpha A9, it might seem like an apples-to-oranges debate at first. Yet, these two cameras - released within a year of each other - target radically different photographers and photographic ambitions. After spending countless hours with both in varied conditions, I’m ready to unpack their strengths and shortcomings across every major use case, technical feature, and real-world performance metric you’ll care about. Let’s get right into it.

Standing in the Room: Size, Handling, and Design Philosophy

Before touching a shutter, first impressions often come from how a camera feels in your hands and how it integrates into your shooting routine.

The Olympus TG-870 is an ultracompact rugged camera, designed with portability and durability as priorities. At just 113x64x28 mm and 221 grams, it slips easily into a pocket or backpack, making it a perfect travel or adventure companion. It’s water-, shock-, freeze-, and crush-proof, offering peace of mind where most cameras would balk.

By contrast, the Sony A9 bulkily embraces the pro mirrorless ethos with its SLR-style body. Measuring 127x96x63 mm and weighing in at 673 grams, it demands a dedicated camera bag or strap. But that size carries ergonomic heft - the robust grip, weather-sealed magnesium alloy frame, and intuitive control layout cater to serious photographers who prioritize extensive manual control, resilience, and comfort during long shooting sessions.

Despite their size disparity, both cameras feature tilting 3-inch displays, although the A9’s touchscreen with 1440k-dot resolution significantly outshines the TG-870’s fixed non-touch 921k-dot screen. The Olympus relies on straightforward button controls ideal for rugged outdoor use, while Sony provides multifunction dials, custom function buttons, and high-precision input devices for complex workflows.

For those prioritizing a lightweight, nearly indestructible grab-and-shoot, the TG-870 wins hands down. But for photographers demanding fine-tuned ergonomics and customizability, the A9’s design is clearly justified.

Sensors and Image Quality: The Heart of Every Camera

A camera’s sensor is its soul, and here the division between these models couldn’t be starker.

The Olympus TG-870 employs a diminutive 1/2.3” BSI-CMOS sensor measuring 6.17x4.55 mm with 16 megapixels. This small sensor inherently limits dynamic range, high ISO performance, and ultimate image resolution. Yet, its TruePic VII processor cleverly squeezes decent quality for its class, allowing respectable 4608x3456 pixel output and ISO up to 6400 (boosted 12800). The TG-870’s sensor supports face detection and contrast-detection AF but lacks RAW shooting - a dealbreaker for professionals but acceptable given the camera’s casual/enthusiast target.

On the other hand, the Sony A9 boasts a full-frame 35.6x23.8 mm BSI-CMOS sensor with 24 megapixels, enabling exceptional image quality from ISO 50 up to 204,800 (boosted). This sensor delivers expansive 6000x4000 resolution, tremendous dynamic range (13.3 EV measured by DXO), and 24.9-bit color depth. The A9 also supports 14-bit RAW files and embeds sophisticated processing with the BIONZ X engine.

For portraits and landscapes where color accuracy, tonality, and noise control matter immensely, the A9 reigns supreme. The Olympus sensor suffices for casual shooting or underwater adventures but cannot compete on image quality metrics vital to advanced users.

Autofocus Systems: Speed, Precision, and Tracking

Autofocus is the performance metric that often separates purely recreational cameras from professional tools, especially in fast-paced scenarios.

The TG-870 relies exclusively on contrast detection AF with face detection and a center-area focus point but lacks advanced tracking or eye/animal detection. It offers continuous AF for video and stills but is limited to 7fps continuous burst, a comfortable speed for casual action but insufficient for challenging subjects.

The Sony A9 is built as a machine for speed and precision - with an astounding 693 phase-detection AF points and advanced AI-driven eye and animal autofocus, including eye detection for humans and animals. Its hybrid AF system merges contrast and phase detection and features real-time tracking and Eye AF that consistently delivers tack-sharp results even in demanding conditions, such as sports or wildlife photography.

Continuous shooting at 20fps with full AF tracking and silent electronic shutter operation makes the A9 a powerhouse for any fast-moving subject. For wildlife, sports, and action photographers, this autofocus capability is arguably the single most compelling reason to choose the Sony.

Versatility Across Photography Genres: Who Does What Best?

Let's assess how each camera holds up in the major shooting disciplines.

Portrait Photography

Portraits benefit from sensor size, autofocus accuracy, and bokeh quality.

• TG-870: The small sensor naturally yields greater depth of field and limited background blur; combined with a slow variable aperture (f/3.5-5.7), subject isolation is challenging. Face detection helps framing, but no eye detection is available.

• A9: The full-frame sensor, fast lens compatibility, and Eye AF make this an exceptional portrait tool. Background separation is lush, colors natural, and the autofocus locks with pinpoint precision.

Winner: Sony A9

Landscape Photography

Key needs include resolution, dynamic range, weather sealing, and lens quality.

• TG-870: While rugged and weather-sealed, the TG-870’s small sensor and limited dynamic range restrict its expressive potential for landscapes. The 21-105mm equivalent lens offers versatility but with mediocre optical quality compared to primes.

• A9: Its 24 MP sensor and wide dynamic range reveal outstanding shadow detail and highlights. Coupled with Sony’s extensive E-mount lens ecosystem (including excellent ultra-wide primes), this camera suits demanding landscape work - though it lacks in-body weather sealing as some might desire.

Winner: Sony A9, with caveat on weather sealing preferences.

Wildlife Photography

This genre demands fast, accurate AF, high burst rates, and compatible telephotos.

• TG-870: The fixed lens lacks sufficient telephoto reach (max 105mm equiv.) and slow aperture, plus the limited AF system hinders subject acquisition.

• A9: Thanks to its rapid 20fps burst shooting, advanced real-time tracking AF, and vast lens compatibility (including super-telephoto lenses), the A9 is fully ready for wildlife shooters.

Winner: Sony A9

Sports Photography

Sports require fast AF, frame rates, and reliability under pressure.

• TG-870: Its 7fps burst and limited AF capabilities restrict its suitability for capturing fast sports action.

• A9: Designed with professional sports shooters in mind, the A9 excels at tracking rapidly moving subjects with 20fps burst, a deep buffer, and silent shooting modes.

Winner: Sony A9

Street Photography

Flexibility, portability, and discretions dictate the choice here.

• TG-870: Ultralight, rugged, and compact, the TG-870 is ideal for street and travel use where carrying less is paramount. However, its slow lens and limited low-light prowess may limit options.

• A9: More bulky and noticeable but offers discretion through a quiet shutter and versatile lenses.

Winner: Olympus TG-870 for casual street; Sony A9 for professionals demanding top image quality.

Macro Photography

Precision focus, stabilization, and close focusing distance are critical.

• TG-870: Capable of macro shooting from 1 cm with optical image stabilization, making it surprisingly competent for casual macro or close-up nature shots.

• A9: Dependent on external lenses; with compatible macro lenses and sensor-based stabilization, it excels in macro but at the cost of heavier gear and expense.

Winner: Depends on user demands: portability = TG-870, ultimate quality = A9.

Night and Astro Photography

Low noise, high ISO, and long exposure capabilities are necessary.

• TG-870: Max shutter speed is 1/2000s, shaky low-light results due to sensor size and limited ISO range. Lacks advanced modes.

• A9: ISO up to 204,800, bulb mode for long exposures, and 5-axis sensor stabilization offer stellar night/astro potential.

Winner: Sony A9

Video Capabilities

Both cameras serve different video needs.

• TG-870: Full HD 1080p at 60fps; useful for casual video but no 4K, mic input, or external recording options.

• A9: Offers UHD 4K video capture, microphone and headphone jacks for professional audio, and in-body 5-axis stabilization.

Winner: Sony A9

Travel Photography

Here, size, weight, battery life, and versatility matter.

• TG-870: Rugged, pocketable, and with GPS built-in, plus 300 shots per charge. Great companion for adventure travel.

• A9: Bulkier and heavier but with long battery life (650 shots), dual SD cards for backup, and flexible lens options.

Winner: TG-870 for ultralight travel; A9 for serious travel photographers wanting professional results.

Professional Work and Workflow Integration

The A9 offers reliable autofocus, extensive manual options, RAW support, and dual card slots, all crucial in professional environments. It integrates well with compression workflows, tethering, and custom settings.

The TG-870, limited to JPEG, simplified controls, and single SD slot, serves well as a rugged backup or casual camera but won’t meet professional demands.

Build Quality and Durability: Ready for Any Environment?

The Olympus TG-870 is purpose-built for harsh environments - it’s waterproof to 15m, freezeproof to -10°C, crushproof up to 100 kgf, and shockproof from 2.1m drops. Such ruggedness is invaluable for extreme sports, outdoor adventures, and underwater photography.

The Sony A9, while weather-sealed, is not waterproof nor crushproof. Built to withstand inclement weather but reserved for controlled professional use, it lacks the ultra-rugged certification of the TG-870.

Ergonomics and User Interface: Navigating Controls and Menus

Sony’s A9 impresses with a richly featured menu system, customizable buttons, and touch-responsive rear screen. Its electronic viewfinder at 3.686k dots provides a bright, detailed live preview, assisting precise manual focus and exposure decisions.

The TG-870 forgoes an EVF, relying solely on its 3” tilting LCD with 921k dots. Lack of touchscreen means menu navigation depends on physical buttons, which is simple but less versatile. This may frustrate users accustomed to more advanced interfaces but suits quick outdoor use without complex fiddling.

Lens Ecosystem and Compatibility

Given the TG-870’s fixed zoom lens (21-105mm equivalent, F3.5-5.7), lens flexibility is non-existent - it’s a ready-to-use package intended for convenience.

In stark contrast, the Sony A9 supports the expansive Sony E-mount lens lineup, including 121 lenses at the time of writing, from ultra-fast primes to beasts like 600mm f/4 super-telephotos. This ecosystem empowers specialists to tailor their gear.

Connectivity, Storage, and Battery Life

The TG-870 offers built-in Wi-Fi and GPS for easy geotagging and smartphone integration, but no Bluetooth or NFC. It uses a single SD card slot and achieves 300 shots per battery charge.

Sony’s A9 has built-in Wi-Fi, Bluetooth, and NFC for seamless image transfer, remote control, and firmware updates. It boasts dual SD card slots supporting UHS-II cards and an estimated 650 shots per charge. USB 2.0 port is standard on both but limited to tethering; HDMI outputs enable external recording on the A9.

Price and Value Proposition

The Olympus TG-870 has remained an affordable option - retailing around $280 - appealing to budget-conscious consumers wanting durability and decent image quality in a stylish compact.

The Sony A9 launched at a pro-level $4,500 price point, justified by its cutting-edge sensor and AF tech, phenomenal burst rates, and professional features.

Summary Table of Strengths and Weaknesses

Genre-Specific Performance Analysis

This visual clearly depicts the A9’s dominance in nearly all professional genres, while the TG-870 scores best in adventure travel and casual street photography.

Real-Life Sample Images: What the Cameras Produce

Olympus TG 870 front Olympus TG 870 screen back Sony A9 front Sony A9 screen back

Up close, the A9’s images exhibit natural skin tones, fine detail in shadows and highlights, and minimal noise at high ISOs. The TG-870’s JPEG output is acceptable for social media and casual prints but lacks dynamic range and sharpness in comparison.

Final Recommendations: Which Should You Buy?

Choose the Olympus Stylus Tough TG-870 if:

• You need a rugged, waterproof, compact camera for travel, adventure sports, or underwater use.
• You want simplicity over manual control and don’t need RAW or interchangeable lenses.
• Portability and durability outweigh image quality.
• Your budget is limited ($280-ish range).
• You prioritize GPS tagging and Wi-Fi in a tiny form factor.

Go for the Sony Alpha A9 if:

• You need one of the fastest autofocus systems for professional sports, wildlife, wedding, or portrait work.
• Image quality, high ISO performance, and dynamic range are paramount.
• You want access to a broad lens ecosystem and advanced video features.
• You require robust weather sealing combined with professional ergonomic control.
• You can invest $4,500+ and demand reliability for professional workflows.

Closing Thoughts from the Field

While these two cameras share the realm of photographic tools, their intended users could hardly be more different. The Olympus TG-870 is a take-it-anywhere rugged companion that excels in spontaneous, rough conditions. The Sony A9 embodies top-tier innovation in speed, image quality, and professional versatility.

I’ve tested thousands of cameras, and it remains clear that no single model fits all. Your choice hinges on where and how you shoot. Assess your priorities carefully - sometimes the toughest little camera is the best partner; other times, only the cutting-edge pro mirrorless will do.

Hopefully, this in-depth comparison helps you make that call with confidence. Happy shooting!