Panasonic GH3 vs Sony A7S II: A Deep Dive into Two Mirrorless Cameras from Different Eras and Classes

When it comes to choosing a mirrorless camera, the market offers a vast spectrum - from the enthusiast-friendly systems to the high-end professional tools. Among the many options, Panasonic's Lumix GH3 and Sony's Alpha A7S II stand out, each having made waves in their prime. Although unveiled three years apart and catering to somewhat different audiences, these two continue to attract interest due to their unique capabilities and strengths.

I’ve personally logged hundreds of shooting hours with both cameras over the years, across landscapes, portraits, sports, and video projects. This comparison is not a mere specs race but an honest evaluation grounded in hands-on experience, technical measurements, and the challenge of real-world situations. So, whether you’re a seasoned pro seeking a specialty tool or an enthusiast exploring your next investment, read on to find which one better fits your photography style.

Size, Handling, and Ergonomics: Form Meets Function

Every serious photographer knows that camera handling directly influences shooting joy and efficiency. Let's start by comparing the physical attributes and design philosophy of each.

The Panasonic GH3 follows the traditional SLR-style mirrorless design but is compact for its class, measuring 133x93x82mm and weighing 550g. The Sony A7S II, also a mirrorless SLR-type, is slightly more compact horizontally but thinner and heavier at 627g, with dimensions 127x96x60mm. While the GH3's deeper grip feels reassuring during handheld shots, the A7S II presents a sleeker footprint that many find more pocketable in larger coat pockets.

Ergonomically, the GH3's button layout prioritizes tactile control. Panasonic integrates a fully articulated 3-inch OLED touchscreen with moderate 614k-dot resolution, great when shooting at awkward angles or for vlogging. The fully articulated screen is a boon for macro and video shooters. Meanwhile, the A7S II uses a 3-inch tilting LCD boasting double the resolution (~1.2 million dots), crisp and vibrant but lacking touch capability - a sore point for those who prefer intuitive fingertip controls.

Top-down, the GH3's numerous dials and buttons reflect its 2012 heritage - long before touchscreens became standard. This might look intimidating to beginners but is a delight to experienced users who want immediate access to shutter speed, ISO, and white balance without diving into menus. In contrast, the A7S II trims the physical controls for a cleaner, minimalist approach, often relying on custom buttons and cameras’ menus for many settings.

Build quality-wise, both offer environmental sealing for dust resistance but are not fully weatherproof. Yet, I never hesitated taking either out in moderately adverse conditions. Panasonic's GH3 boasts further ruggedness with a slightly more robust chassis, helping instill confidence outdoors.

Sensor and Image Quality: Size and Sensitivity Talk

The heart of any camera lies in its sensor. Comparing a Four Thirds sensor to a Full Frame (and at different resolution points) is almost apples to oranges - but practical photographer’s insight emerges when we measure what that difference means for your images.

The Panasonic GH3 houses a 16MP Four Thirds sensor measuring 17.3x13mm, which converts to a substantial 224.9 mm² imaging area. On the other hand, the Sony A7S II’s full-frame CMOS sensor stretches to 35.6x23.8mm, four times bigger by area (847 mm²) but at a modest 12.2MP resolution. This lower pixel density is purposeful - Sony tunes the A7S II for extreme light sensitivity and dynamic range, aiming for video professionals and astrophotographers first.

DxOMark sensor scores validate this: The GH3 scores 71 overall with 22.7 bits color depth, 12.4 stops dynamic range, and low-light ISO performance rated at the equivalent ISO 812. The Sony A7S II shines with a score of 85, elevating color depth slightly (23.6 bits), dynamic range (13.3 stops), and a whopping low-light ISO near 3000. The A7S II's maximum ISO reaches 102,400 natively with boosters to 409,600, making it a low-light beast unmatched by the GH3's capped ISO 12,800.

In plain terms, if you're photographing dimly lit indoor events, concerts, or shooting astrophotography, the A7S II lets you get cleaner shots at night when the GH3’s noise becomes intrusive. Conversely, if you favor detailed landscapes or portraits where resolution matters, the GH3’s higher megapixel count is advantageous, especially when printing large.

Autofocus Systems: Speed, Accuracy, and Tracking Performance

Let's focus on how each performs when it comes to locking focus - a critical factor to professionals shooting fast action or demanding portraits.

Both utilize contrast-detection autofocus systems. The GH3 offers 23 focus points and support for face detection with touch autofocus functionality that feels responsive in live view. The A7S II steps up significantly with 169 autofocus points spread across the frame, including center weighting and face detection as well. However, neither model sports phase-detection autofocus, which somewhat limits how quickly they can track fast-moving subjects compared to modern hybrid or phase-based AF systems.

Continuous autofocus and tracking are crucial for wildlife and sports photography. The GH3’s burst is remarkable at up to 20 fps in a special high-speed mode, although autofocus performance in continuous shooting is relatively slow and best suited for static or slow-moving subjects. The A7S II offers a modest 5 fps burst but compensates with excellent low-light AF reliability and precision, thanks to its sensor and processor pairing.

In practice, I found the GH3 manageable but requiring patience when shooting bursts or erratic wildlife movement, while the A7S II's larger focus array and refined algorithms handle tracking better in low-light and fast-paced environments - even if not as snappy as newer rivals.

Photo Disciplines: Which Excels Where?

Alright, the technical canvas has been laid out - now how do these cameras handle the demands of different photography genres?

Portraits: Rendering Skin and Bokeh

Portrait photographers often desire flattering skin tones, fine detail, and smooth background separation.

The GH3's 16MP sensor, paired with the Micro Four Thirds lens ecosystem (over 100 lenses available), can deliver excellent portraits with emphatic sharpness. Panasonic’s color science from that era leans toward warmer skin tones, which many find pleasing out of camera. The GH3 also has face detection autofocus with touch-select capabilities that aid composition.

Meanwhile, the A7S II, with its full frame sensor, naturally yields shallower depth of field for a given aperture, resulting in creamier bokeh - especially with fast prime lenses. The downside is only 12MP resolution, which presents less pixel-level detail. Still, its wider dynamic range benefits portraits in tricky lighting, preserving highlights and shadows delicately.

Landscape Photography: Detail and Durability

Landscape shooters prize resolution, dynamic range, and weather sealing.

The GH3’s 16MP resolution meets many landscape needs, especially for sharing online or moderate print sizes. Its 12.4-stop dynamic range is respectable, though falls short compared to newer mirrorless cameras. Strong points include a weather-sealed body that is trustworthy in damp or dusty environments.

The A7S II’s lower resolution might seem a drawback here, but its superior dynamic range (13.3 stops) and full-frame sensor mean richer tonal gradation and low-noise shadow detail - critical for sunrise and sunset exposures. However, its weather sealing is similar but not robust enough for heavy rain.

Wildlife and Sports: Autofocus and Speed

Wildlife and sports photographers test a camera’s autofocus prowess, burst rates, and buffer depth.

The GH3 impresses with a blistering 20 fps burst mode, a rarity in its era and still enviable today, making it a potential tool for freezing fast action. But the contrast-detection AF system limits the ability to track erratic subjects reliably, leading me to recommend the GH3 primarily for subjects with predictable movement or when using manual and single autofocus.

The A7S II’s slower 5 fps burst might dissuade sports shooters, yet its advanced AF system delivers better accuracy and low-light focus lock. Its superior ISO performance also benefits night and indoor sports.

Street Photography: Discretion and Portability

Street photographers usually value discreet size, weight, and silent operation.

The GH3, a bit bulkier and older in design, still manages reasonable portability. It includes a mechanical shutter up to 1/4000s, but lacks silent electronic shutter options that modern cameras feature. It has a built-in flash, but that tends to attract unwanted attention.

The A7S II is lighter and more compact, advantageous on urban strolls, but it also lacks a silent shutter mode. However, color rendition and performance in low ambient light favor it, especially when available light is all you have. The quietness of the lens and nuanced handling count when you want to blend in.

Macro Photography: Precision and Stabilization

For close-up specialists, focus precision and stabilization matter immensely.

Here the GH3's fully articulated OLED touchscreen aids manual focusing, crucial in macro work. Unfortunately, it lacks in-body image stabilization (IBIS), so users must rely on stabilized lenses or tripods for crisp captures.

The A7S II packs sensor-based 5-axis stabilization, a major plus for handheld macro shooting. Coupled with high-end Sony and third-party macro lenses, it ensures sharp results in challenging environments.

Night and Astrophotography: ISO and Exposure Mastery

Night shooters and astrophotographers will find the A7S II a standout with its colossal ISO range and clean output at very high sensitivities. ISO 102,400 and boosted modes make capturing stars and dim scenes feasible handheld or with short exposures - something the GH3 can't replicate due to noise limitations at ISO 12,800 max.

Furthermore, the A7S II includes advanced video exposure modes catering to timelapses and long exposure sequences with minimal heat noise. The GH3 offers timelapse but not the same depth of exposure control.

Video: The Silent Workhorse vs The 4K Pioneer

Cinephiles and hybrid shooters will see these cameras diverge sharply.

The GH3 was a milestone with full HD video at 60p, 50p, 30p, 25p, and 24p modes, plus HDMI out and built-in mic/headphone jacks. It records 1080p in AVCHD and MPEG-4 formats and sports a fully articulated touchscreen ideal for framing vlogs or low-angle shots. However, it lacks 4K video altogether.

The Sony A7S II targets filmmakers aggressively with 4K internal recording at 30p/24p (XAVC S codec) and impressive slow-motion Full HD at 120p. The sensor-based 5-axis stabilization dramatically smooths handheld footage, while professional audio interfaces let you monitor sound scrupulously. HDMI output supports clean 4K external recording - a dream for many.

For video-centric shooters, the A7S II is a clear winner despite its age.

Travel and Everyday Use: Versatility and Battery Life

Travel photography demands a balance: size, weight, battery, and flexibility.

The GH3 excels in battery life with around 540 shots per charge versus the A7S II’s 370 frames, the latter being more taxing due to larger sensor and video capabilities. Both support SD cards, but the A7S II adds Memory Stick compatibility, reflecting Sony’s ecosystem approach.

Though heavier, the A7S II’s superior low-light performance and image stabilization justify packing it for varied travel conditions. The GH3 is more robust and user-friendly for long shoots without charging stops.

Technical Details You Should Know Before Buying

Lens Ecosystem

Both cameras mount on popular lens systems - Micro Four Thirds for the GH3 and Sony E-mount for the A7S II. Panasonic’s system is mature with over 100 native lenses, many affordable and compact. Sony’s E-mount benefits from a wider full-frame native lens lineup and excellent third-party options like Sigma and Tamron, albeit often pricier.

Build Quality and Weather Resistance

Both cameras feature weather sealing adequate for fieldwork but non-waterproof designs mean you should avoid heavy rain.

Connectivity

Built-in Wi-Fi comes standard on both for image transfer and remote control, but neither has Bluetooth (though the A7S II offers NFC). Both include HDMI and microphone/headphone ports, essential for video work.

Battery and Storage

The GH3’s stronger battery performance and single SD card slot reflect its prime design for stills and casual workflow. The A7S II's NP-FW50 battery, while smaller, balances more power-hungry tasks like 4K video.

Summary Scores and Genre-Specific Ratings

Panasonic GH3: Solid 71 DxOMark score reflecting competent image quality and fast operation for its class.
Sony A7S II: Notably higher 85 score, emphasizing superb low-light and dynamic range.

• Portraits: Slight edge to A7S II for signature bokeh and dynamic range.
• Landscape: A7S II wins on tonal depth; GH3 holds ground on resolution.
• Wildlife & Sports: GH3 favored for burst speed; A7S II for low-light AF.
• Street Photography: A7S II’s compactness and IQ advantage.
• Macro: A7S II’s IBIS an advantage, GH3’s articulated screen helpful.
• Night/Astro: A7S II dominates unequivocally.
• Video: A7S II leads with 4K and stabilization.
• Travel: GH3’s battery life vs A7S II’s versatility - a close call.
• Professional Workflow: A7S II better integrated with external apps and codecs.

Real-World Gallery: Images Straight from Both Cameras

Panasonic GH3 front Panasonic GH3 screen back Sony A7S II front Sony A7S II screen back

Here you can observe the GH3’s punchy colors and fine detail in daylight, while the A7S II excels in high-ISO scenarios, subtle tonal gradations, and video captures. Notice the depth of shadow detail in the Sony images - especially in night scenes - where the GH3 struggles with noise.

Final Recommendations: Which Camera for Whom?

To wrap up, picking between the GH3 and A7S II reduces to prioritizing your needs and budget.

Choose the Panasonic GH3 if:

• You want a rugged, compact Micro Four Thirds camera with a rich lens lineup and tactile controls.
• You shoot mostly stills like landscapes, portraits, and street photography during daylight or well-lit situations.
• Video is a supportive feature, but you don’t need 4K.
• Battery life and affordability (approx. $800 new retail) matter to you.

Opt for the Sony A7S II if:

• Your priority is low-light photography, astrophotography, or professional video production with internal 4K.
• You want superior dynamic range and color depth for fine tonal captures.
• You appreciate high-end features like 5-axis IBIS and expanded ISO ranges.
• You are comfortable investing substantially more (approx. $2,700 new retail) for pro-level performance.
• Your workflow favors external audio, clean HDMI out, and advanced codec options.

In the end, both the GH3 and the A7S II are commendable cameras, each a flagship of its own class when released. Despite the GH3’s age, it remains a powerful tool for those seeking an accessible, versatile mirrorless system. Meanwhile, the A7S II holds an enduring place in the arsenal of photographers and videographers chasing uncompromising low-light capability and 4K video in a compact body.

Choosing between them requires weighing your immediate photographic priorities against long-term goals - and hopefully, this in-depth comparison helps you make that decision with clarity and confidence. Happy shooting!