Panasonic GH6 vs GH3: A Hands-On Comparison Between Two Generations of Micro Four Thirds Champions

As someone who’s tested cameras across decades and shooting conditions, I’ve had the chance to work intimately with both the Panasonic Lumix GH3 - one of the early heroes of the micro four thirds video revolution - and the Panasonic GH6, its much-hyped, tech-packed successor aimed squarely at pro content creators and advanced enthusiasts. These two cameras bookend an era of tremendous innovation, and today I want to break down their differences from a practical, real-world perspective.

Whether you’re a budding YouTube creator weighing whether to upgrade, a wildlife shooter curious how far Micro Four Thirds (MFT) has come, or just a cheapskate wanting maximum bang on a budget, this in-depth comparison covers all the essential ground.

Let’s dive right in, starting with the physical presence and ergonomics.

The Feel Factor: Body, Handling, and Ergonomics

When I first picked up the Panasonic GH3, it impressed me with its compact but solid build, which was a pretty big deal in 2012. The camera carries the classic SLR-style mirrorless form factor, but with a relatively light body: 550 grams. It’s comfortable to clutch all day, especially if you pair it with one of those pancake primes or a modest zoom.

Now compare that with the GH6: this pro beast weighs in at 823 grams and measures 139x100x100 mm - noticeably bigger and chunkier to accommodate an expanded feature set, cooling system, and dual card slots. The grip is deeper and more contoured, which makes a huge difference if you shoot handheld for hours or haul big lenses around.

Here’s a side-by-side look to help you visualize how they stack up physically:

From a tactile perspective, the GH6 feels more substantial and weather-resistant, with a robust magnesium alloy body that’s been sealed against dust and moisture. The GH3 tries to keep up here but falls behind - while it offers some environmental sealing, it can’t really meet the demanding conditions the GH6 is designed for.

Control Layout and Accessibility

Both cameras have fully articulating 3-inch screens, but Panasonic improved the screen resolution massively on the GH6 (1840k dots vs. 614k on GH3), making it far easier to check focus and playback outdoors.

The top control surfaces have also evolved. The GH3’s layout is straightforward but basic. Meanwhile, the GH6 incorporates more customizable buttons and dials, including dedicated dials for ISO, shutter speed, and exposure compensation. The buttons are also more spaced out and easier to operate with gloves or wet fingers - a boon for outdoor shooters.

Take a look at how the control decks compare:

I especially appreciate the illuminated buttons on the GH6 for night use, a luxury the GH3 misses entirely. The GH6 is clearly designed with heavy day-to-day professional use in mind, whereas the GH3 aims for versatility in a smaller package.

Imaging Heart: Sensor Technology and Image Quality

One of the biggest leaps between these two is in sensor technology. Panasonic has stuck with a Four Thirds sensor size - 17.3x13 mm - for both models, which means the field of view and focal length multipliers remain consistent (2.1x crop factor).

However, while the GH3 features a 16MP sensor with a built-in anti-aliasing filter, the GH6 ups the ante with a 25MP sensor that drops the AA filter to get sharper, cleaner images. This results in more detailed stills, especially if you like to print large or crop aggressively.

Dynamic Range and ISO Performance

From my lab tests and real-world experience, the GH6 offers a notable improvement in dynamic range - allowing it to capture more detail in shadows and highlights simultaneously. This matters a ton for landscape photographers who often wrestle with high-contrast scenes.

The native ISO range also expands significantly on the GH6: 100–25,600 compared to the GH3’s 200–12,800. In practical terms, this means cleaner night and low-light shots on the GH6, with less noise creeping into your files above ISO 3200. (The GH3, by contrast, starts showing noticeable grain beyond ISO 800–1600.)

Both cameras shoot raw, but GH6's sensor and noise reduction systems give it a clear edge for demanding studio or astrophotography sessions.

Autofocus: Tracking, Speed, and Accuracy

Having tested both cameras extensively with fast action and tricky subjects, the autofocus system difference jumps out immediately.

The GH3 relies on contrast-detection autofocus only, with 23 AF points. It’s okay for static subjects but can struggle with moving targets. I found hunting - where the lens “searches” back and forth for focus - a common frustration, especially in low light.

The GH6, on the other hand, offers more sophisticated phase-detection AF (well, Panasonic markets Hybrid Contrast Detection), plus advanced eye and animal eye tracking. This is a game-changer for portrait photographers who want spot-on focus on eyes - or wildlife shooters locking in on fluttering birds or elusive mammals.

Face and animal eye detection is also solid on the GH6 but nonexistent on the GH3. The GH6 supports continuous autofocus and tracking even in video mode, which I found invaluable during sports events or fast-moving wildlife sessions.

Video Capabilities: The Pro Content Creator’s Arsenal

If you’re a hybrid shooter or video creator, the differences between these two will feel like night versus day - and then some.

The GH3 was one of the early champions of HD video, offering up to 1080p60 with AVCHD and MPEG-4 codecs. Great for filmmakers on a budget, but by today’s standards, the options feel limited and frustrating for post-production work.

The GH6 absolutely blows the GH3 out of the water with:

• 6K video at 60fps (5760 x 2880 resolution)
• 4K at 120fps for smooth slow-mo
• Higher bit-rate recording with H.264 and H.265 codecs
• In-body 5-axis image stabilization that smooths handheld footage immensely
• Dedicated microphone & headphone jacks for audio monitoring
• Unlimited recording times, thanks to active heat management

The GH6 is a bona fide cinema camera in many respects, and functions like focus stacking and bracketed exposures widen creative possibilities further.

For vloggers and content creators, GH6’s fully articulating high-res touch display and extensive video features put it leagues ahead.

Handling and User Interface: How Intuitive Are They?

Both cameras sport fully articulating LCDs with touchscreen capabilities, ideal for creative angles or selfies.

But the GH6’s screen is far brighter, crisper, and easier to navigate, with faster menu systems and refined touch gestures that reduce menu diving. In contrast, the GH3’s older OLED screen has a lower resolution and slower interface response, sometimes feeling a bit clunky.

Additionally, the GH6 allows customizing several buttons and dials to speed up workflow, including an assignable joystick for rapid AF point moves (absent on GH3). This may not matter immediately, but for professionals shooting tight deadlines, it’s a godsend.

Lens Ecosystem and Compatibility

Both cameras use the Micro Four Thirds mount - one of the most mature and versatile ecosystems in the mirrorless market.

The GH3 had access to around 107 native MFT lenses on launch; the GH6 now supports a whopping 118 lenses and benefits from Panasonic’s latest lens optimizations.

Because of backward compatibility, you can physically mount nearly any MFT lens on either camera, but GH6 unlocks extra benefits such as improved lens correction profiles, faster autofocus with newer lenses, and expanded focus bracketing/stacking modes that GH3 can’t touch.

If you already own a lens collection or want flexibility without breaking the bank, both cameras deliver plenty of choice.

Burst Shooting and Buffer Performance

For capturing action, frame rate and buffer depth are critical.

The GH3 boasts a faster continuous shooting speed - up to 20fps (albeit mostly at reduced resolution and with electronic shutter quirks). The GH6 offers up to 14fps with the mechanical shutter, still respectable for most uses.

But more importantly, the GH6’s buffer can handle longer bursts without slowing down, thanks to faster processors and CFexpress card support in the primary slot.

In wildlife or sports photography, the GH6’s continuous tracking paired with good burst rates yield more keepers than the GH3’s raw shooting speed advantage.

Storage and Connectivity

GH3 comes with a single SD card slot supporting SDHC/SDXC cards, whereas GH6 ups capacity and speed with two slots: one CFExpress Type B (ultrafast) and one compatible SD slot supporting UHS-II and Video Speed Class 90.

For professionals shooting 6K video or RAW bursts, the faster CFexpress slot is a must-have.

Wireless-wise, GH6 adds built-in Bluetooth alongside Wi-Fi, supporting faster file transfers and remote control via Panasonic’s smartphone app. GH3 has Wi-Fi only and lacks Bluetooth, meaning slower pairing and fewer features.

USB interfaces also evolved from USB 2.0 on the GH3 to USB 3.2 Gen 1 on the GH6, allowing faster tethered shooting and file downloads.

Battery Life and Power Management

Interestingly, the older GH3 offers about 540 shots per battery charge, besting GH6’s 360 shots (CIPA rating). Why?

The GH6 packs a lot more processing power, runs a high-res electronic viewfinder, and supports power-hungry features like 5-axis stabilization and 6K video. Hence, battery life takes a hit.

Practically, if you shoot lots of stills, GH3 lasts longer between charges; if you’re video-heavy or heavy on the features, you’ll want spare batteries or external power solutions for the GH6.

Real-World Genre Performance

To really understand how these cameras fare, I tested both across a range of photography disciplines. Here’s a quick breakdown with my evaluations for each - both in terms of ease-of-use and final image quality:

Panasonic GH6 front Panasonic GH6 screen back Panasonic GH3 front Panasonic GH3 screen back

Portrait Photography

The GH6 wins hands down. Its improved eye detection autofocus, higher resolution sensor, and better noise control at mid-to-high ISOs mean cleaner, sharper headshots and creamy bokeh. The fully articulating touchscreen makes framing selfies or vlogging easier too.

The GH3 can produce respectable portraits but struggles with fast focus on eyes and noise at higher ISO. Bonus points for the GH6’s improved color science and skin tone rendition, which is softer and more natural.

Landscape Photography

Here again, GH6's extra resolution and dynamic range pay off. Scenes with bright skies and deep shadows show more detail and natural color gradations. Weather sealing also makes it more rugged when shooting outdoors in adverse conditions.

The GH3 has decent dynamic range for its era but lacks the detail and high ISO performance for night landscapes or astrophotography.

Wildlife and Sports

Tracking autofocus and fast burst rates are vital here. While GH3’s higher 20fps burst speed looks attractive, the GH6’s advanced AF system locks focus more reliably on moving subjects and produces more keepers.

The GH6 also supports heavier telephoto lenses better thanks to improved stabilization and ergonomic grip.

Street Photography

The GH3 shines in street due to its smaller size and lighter weight, making it less conspicuous on the street.

GH6’s bigger size can draw attention, but the articulated screen and tilting EVF are useful for candid shots.

In low light, GH6’s better ISO performance means cleaner files when shooting handheld after dark. The GH3 needs slower shutter speeds or flash.

Macro Photography

The GH6 edges forward with more precise focus bracketing and stacking capabilities - fantastic for macro work. Built-in stabilization helps keep things sharp.

The GH3 doesn’t support focus stacking and lacks stabilization, so results depend more on lens and technique.

Night and Astro Photography

The GH6’s low-light ISO and dynamic range improvements make it the smart choice for astrophotography, with cleaner star fields and improved exposure control.

The GH3’s sensor noise and lower max ISO hamper long exposures in the dark sky.

Video Production

No contest: GH6 crushes the GH3. Higher resolutions, slow motion at 4K120 and 6K60, advanced codecs, and in-body image stabilization offer filmmakers and vloggers fantastic creative freedom.

GH3’s video is serviceable for casual use, but lacks 4K and faces overheating/time limits.

Travel Photography

GH3’s lightweight design suits minimalist travelers or those who prioritize size and battery life.

GH6 offers versatility and pro features, at the cost of heft and power consumption, but is better suited for multimedia travel creators who want top image and video quality on the go.

Professional Workflows

Dual card slots, expanded RAW options, faster file transfer, and rugged construction make the GH6 a clear winner for pro shooters who depend on reliability and flexibility.

While the GH3 is a capable tool, the GH6 is built to keep pace with modern professional workflows.

Overall Performance Scores and Genre Breakdown

For quick reference, here’s a visual summary of the two cameras’ overall and genre-specific performance based on my testing:

Pros and Cons at a Glance

Who Should Buy Which Camera?

Go for the Panasonic GH3 if:

• You’re budget-conscious but want a capable Micro Four Thirds mirrorless camera.
• Your photography focuses on casual shooting, travel, or beginner video.
• You prefer smaller, lighter gear and longer battery life.
• You don’t need 4K video or the absolute latest autofocus tech.
• You already own MFT lenses and want a decent backup camera.

Invest in the Panasonic GH6 if:

• You need cutting-edge video features like 6K, slow-motion, and excellent stabilization.
• You shoot portraits, wildlife, or sports requiring fast, reliable autofocus.
• You want superior image quality with more resolution and dynamic range.
• Professional workflow support with dual card slots and rugged design matters.
• You rely on advanced features like focus stacking, bracketing, and high ISO performance.
• Your budget allows for a pro-level camera to futureproof your kit.

Final Thoughts: The Evolution of a Mirrorless Workhorse

The Panasonic GH3 was a trailblazer - especially considering its launch in 2012, it packed a lot of tech into an affordable and compact package. It gave hobbyists and pros a way into mirrorless video and stills with decent quality and controls.

The Panasonic GH6, however, represents a paradigm shift. It’s a full-on professional tool designed for today’s hybrid shooters who demand stellar video options and strong still-photo performance. It embraces modern connectivity, speed, and ruggedness but asks for a harder financial commitment and greater size.

If you’re ready to spend $2,200 and want a camera to grow into, the GH6 is undoubtedly worth it - your content creation possibilities will expand exponentially. But if you’re a beginner, casual shooter, or cheapskate, the GH3 may be more your speed, especially if you can snag one used or refurbished.

Additional Resources and User Tips

• If you’re considering upgrading from GH3 to GH6, test your existing lenses for compatibility and autofocusing improvements.
• For video-centric users, investing in fast CFexpress cards is essential to unlock GH6’s full potential.
• Don’t forget the importance of durable camera bags and extra batteries with GH6’s heavier setup.
• For wildlife and sports shooters, pairing GH6 with telephoto MFT lenses plus fast memory cards will maximize your results.

I hope this detailed comparison has helped shine a light on where both cameras excel and where they fall short. If you have specific shooting scenarios in mind, feel free to reach out or comment below - I’m happy to share more hands-on insights from my testing notebooks.

Happy shooting!

End of Review