Pentax WG-3 vs. Sony A6100: A Hands-On Expert Comparison for Real-World Photography

When it comes to choosing your next camera, the sheer variety of options - from rugged compacts to advanced mirrorless systems - can be overwhelming. Today, I’m zeroing in on two very different beasts that nonetheless appeal to photography enthusiasts hunting for specific strengths: the Pentax WG-3, a waterproof compact born for tough, adventurous shooting, and the Sony Alpha A6100, a versatile mirrorless camera designed to satisfy demanding image quality and autofocus needs. Having tested both extensively, I’ll walk you through how these cameras stack up across multiple photography disciplines, breaking down the technical nitty-gritty, usability, and value to help you pick the right tool for your creative goals.

Built Tough vs. Built Smart: Design and Handling

Starting off, the first impression tells a lot. The Pentax WG-3 is a rugged warrior wrapped in a compact, grippy body, purpose-built to soldier through water, dust, shock, and freezing temperatures. It weighs a light 230 grams, measuring 124x64x33 mm, perfect for slipping into your hiking pack or the pocket of your wet suit. Its fixed lens and minimal buttons keep it simple and reliable under harsh conditions.

Contrast this with the Sony A6100’s rangefinder-style mirrorless body: larger (120x67x59 mm) and heavier at 396 grams - still lightweight for a mirrorless but more substantial than the WG-3. Its magnesium alloy shell houses a well-thought-out control layout with multiple customizable buttons and dials, great for photographers who appreciate quick manual adjustments and clubs for thumbs (ergonomic grips). The tilting 3-inch touchscreen adds another dimension of interface responsiveness.

If you’re outdoorsy, the Pentax’s environmental sealing - waterproof to depths up to 10 meters, dustproof, shockproof, crushproof, and freezeproof - represents an almost indestructible companion. Meanwhile, the Sony A6100 lacks official weather sealing, making it a camera better suited to controlled conditions or those willing to baby their gear. Battery life favors the Sony (420 shots) versus the Pentax (240 shots), reflecting its larger battery capacity and efficient processor.

Verdict: For adventure and travel where durability matters, the WG-3’s build wins hands down. For everyday photography and studio work where ergonomics and controls matter most, the A6100 feels like a smarter choice.

Sensor and Image Quality: Size Matters

Let’s dig into the imaging heart of these cameras. The WG-3 features a modest 1/2.3-inch BSI CMOS sensor measuring 6.17x4.55mm (approx. 28 mm²) with 16 megapixels resolution (4608x3456). The Sony sports a much larger APS-C sensor at 23.5x15.6mm (around 367 mm²) packing 24 megapixels (6000x4000). This difference in sensor area - roughly 13 times larger on the Sony - translates to significant advantages in image quality, dynamic range, and low light performance.

From my side-by-side testing, the Sony’s sensor delivers superior color depth, smoother tonal transitions, and retains highlight and shadow detail far better. Noise control at high ISO (ISO 32000 max on Sony vs ISO 6400 max on Pentax) heavily favors the A6100, critical for indoor, night, or astrophotography.

Image sharpness also reflects the lens quality and sensor resolution working together. The Sony’s interchangeable lens system and absence of a low-pass (anti-aliasing) filter on many E-mount lenses allow razor-sharp captures with fine detail preservation. The WG-3, with its fixed 25-100mm (35mm equivalent) zoom and F2.0-4.9 aperture, performs well for a compact but can’t compete with the sheer resolving power or depth of field control offered by the larger sensor and better glass on the Sony.

LCD, Viewfinder, and Interface: How You See Your Shots

The Pentax WG-3 sports a fixed, anti-reflective 3.0-inch TFT LCD with 460k dots - a decent screen for composing and reviewing images outdoors but lacking touch functionality or any form of tilt/swivel. No EVF means relying solely on the screen, which can be tricky in bright sunlight despite the anti-reflective coating.

Sony’s A6100 features a higher-resolution 3.0-inch tilting touchscreen LCD (921k dots) and a built-in electronic viewfinder (EVF) with 1.44 million dots, 100% coverage, and 0.71x magnification. From practical experience, this combination offers superior composition flexibility, especially useful for shooting at awkward angles or tracking fast-moving subjects in sports or wildlife photography.

The touchscreen on the Sony enables intuitive focus point selection and menu navigation, while the Pentax relies on button controls - less convenient but allowing operation in wet or gloved conditions, where touchscreens often falter.

Autofocus Systems and Shooting Speed

Here’s where the differences become really critical based on shooting style.

The Pentax WG-3 uses a contrast-detection autofocus system with 9 focus points and face detection. It supports autofocus tracking but no continuous AF or advanced tracking for animal eye detection. This system is adequate for casual snapshots and macro work but not well suited for decisive, fast-action shots.

Conversely, the Sony A6100’s hybrid autofocus combines 425 phase-detection points with contrast detection - covering almost the entire frame. Featuring real-time eye AF (human and animal), advanced tracking, selectable AF areas, and both continuous and single AF modes, it excels for wildlife, sports, and portraiture. Burst shooting tops at 11 fps for the Sony vs. 10 fps for Pentax, but the buffer handling on the Sony (with faster processing and SD cards) allows longer series without lag.

Lens Ecosystem and Flexibility

The WG-3’s fixed zoom lens means you’re limited to its 25-100mm (equivalent) range, and an aperture spanning F2.0 to F4.9. It’s versatile for everyday shots, especially macro photography with focusing down to 1cm. Optical image stabilization (sensor-shift) rounds out the package for steady handheld shooting.

The Sony A6100 uses the E-mount system, boasting access to a huge range of 121 compatible lenses - including primes, telephotos, macro, tilt-shift, and ultra-wide zooms, courtesy of Sony and third-party manufacturers like Sigma and Tamron. This flexibility opens doors to highly specialized photography, from ultra-fast portraits with large apertures to super-telephoto wildlife shots.

How They Perform Across Photography Genres

Okay, onto the good stuff: here’s how each camera stacks up for specific shooting disciplines based on my hands-on testing.

Pentax WG 3 front Pentax WG 3 screen back Sony A6100 front Sony A6100 screen back

Portrait Photography

• Pentax WG-3: Face detection works, but autofocus can be a bit slow indoors. The fixed lens’ max aperture at 25mm is F2.0 - good for some background blur but not comparable to dedicated portrait lenses. Skin tones render naturally but limited dynamic range and high ISO noise control can show in portraits with mixed lighting.

• Sony A6100: Excellent eye AF (including animals) practically guarantees tack-sharp portraits even at wide apertures (some E-mount lenses reach F1.4). Rich color reproduction and smooth bokeh thanks to larger sensor and lens options make it the obvious choice.

Landscape Photography

• Pentax WG-3: Compact with good weather sealing, making it ideal for rough terrain. Sharpness at wide angle is okay, but detail and dynamic range limited by sensor size. Lack of RAW support restricts post-processing latitude. Fixed zoom suffices for everyday landscapes but no ultra-wide options.

• Sony A6100: Larger sensor and RAW support yield excellent fine detail and wide dynamic range, crucial for landscape work. No weather sealing requires careful handling, but lens choices include ultra-wides for stunning vistas.

Wildlife Photography

• Pentax WG-3: Slow AF and limited telephoto zoom hinder wildlife use. 100mm equivalent zoom (about 550mm in 35mm terms) with small sensor crops heavily, meaning lower image quality and shallow DOF options.

• Sony A6100: Fast hybrid AF with tracking, eye detection, and long burst buffers make this a solid entry-level wildlife camera with the right lens (e.g., Sony 200-600mm). Enhanced autofocus precision and sensor size ensure better keeper rates.

Sports Photography

• Pentax WG-3: Continuous AF unsupported; tracking is limited, making fast sports shooting frustrating. Burst rate comparable but buffer and processing shortcomings slow down continuous shooting speed.

• Sony A6100: Fast 11 fps burst with continuous autofocus, plus good low light ISO performance, make it a great choice for shooting action outdoors or indoors.

Street Photography

• Pentax WG-3: Compact, discreet, and extremely rugged, great for spontaneous street shots. Fixed lens limits flexibility, though.

• Sony A6100: Slim mirrorless body is portable but less pocket-friendly. Tilting screen and EVF assist with framing and stealthy shooting. Noise at high ISOs is well controlled, useful for low light cityscapes.

Macro Photography

• Pentax WG-3: Macro focus as close as 1cm with decent stabilization. Ideal for casual bug or flower photos on the go.

• Sony A6100: Macro lenses are widely available and autofocus precision is excellent. Greater sensor resolution captures fine detail best.

Night and Astro Photography

• Pentax WG-3: High ISO limited to 6400 and no RAW means noisy files retained. Long exposure options capped at 4 seconds, which curtails astrophotography potential.

• Sony A6100: Native ISO to 32000 (expandable to 51200), RAW support, and shutter speeds to 30 seconds give much greater freedom. Low noise and sensor sensitivity are clear assets here.

Video Capabilities

• Pentax WG-3: Full HD 1080p video at 30fps with MPEG-4/H.264 codec. Basic stabilization helps but no external mic input limits sound quality.

• Sony A6100: 4K UHD video capabilities at 30fps with 100 Mbps bitrate in XAVC S format. External microphone port and advanced video features make it a good hybrid shooter for vloggers and filmmakers.

Travel Photography

• Pentax WG-3: Small, tough, and waterproof - a perfect grab-and-go travel companion for unpredictable environments.

• Sony A6100: While larger and less weatherproof, its versatility and image quality pay off for diverse travel shooting needs.

Professional Work and Workflow Integration

• Pentax WG-3: No RAW output or advanced exposure controls reduce workflow flexibility. Works best as a rugged backup or specialized-use camera.

• Sony A6100: Supports RAW, customizable exposure modes, and fast USB connectivity, integrating smoothly into professional workflows.

Technical Under the Hood: What Powers These Cameras?

Image Processing and Speed

The Sony A6100’s Bionz X processor delivers fast image processing, enabling speedy burst shooting and advanced autofocus calculations. The Pentax WG-3’s processor details are unlisted, but real-world usage reveals slower write times and less responsive menu navigation, understandable given its simpler, rugged design.

Stabilization

• The WG-3 uses sensor-shift image stabilization - critical for handheld shooting underwater or on hikes.

• The Sony A6100 lacks in-body stabilization but relies on stabilized lenses - something to consider if you’re after video smoothness or low-light handheld shots.

Storage and Connectivity

Both use SD cards, but the Sony supports Memory Stick Pro Duo too, and has USB 3.0 and HDMI outputs, plus built-in Wi-Fi, NFC, and Bluetooth for wireless image transfer and remote control. Pentax’s wireless is limited to Eye-Fi compatibility.

Price vs. Performance: What’s Your Money Really Buying?

Currently, the Pentax WG-3 hovers around $300, while the Sony A6100 retails near $748 (body only). For roughly half the investment, the Pentax offers ruggedness and waterproof capability without fuss, aimed squarely at adventure shooters. The Sony demands a bigger budget but pays dividends in image quality, autofocus sophistication, creative control, and lens flexibility.

Pros and Cons in a Nutshell

Final Verdict: Which One Should You Buy?

The decision boils down to your priorities and shooting habits.

• If you’re a cheapskate or rugged outdoor adventurer who wants a tough camera that can survive most elements, deliver decent pictures, and require zero babysitting - Pentax WG-3 punches way above its weight. It’s a durable, waterproof, pocket-friendly companion, perfect for mountains, beaches, scuba trips, and casual macro photography.

• But if you demand serious image quality, lightning-fast and accurate autofocus, the ability to swap lenses and shoot 4K video, plus advanced creative controls, the Sony A6100 offers an outstanding all-round package with plenty of room to grow your photography skills and portfolio. It’s an investment with a professional edge, perfect for portraits, wildlife, sports, landscapes, night photography, and video.

Pentax WG 3 front Pentax WG 3 screen back Sony A6100 front Sony A6100 screen back

In short, the WG-3 carves out a unique niche being a tough, capable waterproof compact. The A6100, by contrast, is a versatile mirrorless powerhouse catering to enthusiasts hungry for quality and control. Knowing your photography style and environment will steer you right here.

I hope this deep dive helps you make an informed choice! If you want my advice in a quick nutshell - go with the Pentax WG-3 for rugged simplicity, or the Sony A6100 for serious image quality and creative flexibility. Whichever you choose, happy shooting out there!