Panasonic S1 vs. Panasonic GM5: A Hands-On Deep Dive Comparing Two Generations of Mirrorless Photography

As someone who has rigorously tested cameras spanning from entry-level compacts to pro-grade systems for over 15 years, I’ve developed a keen appreciation for the nuanced trade-offs that different mirrorless cameras present. Today, I’m walking you through a direct, experiential comparison of two distinct Panasonic mirrorless cameras that represent very different eras and ambitions: the Panasonic Lumix DC-S1 - Panasonic’s flagship full-frame powerhouse, released in 2019 - and the Panasonic Lumix DMC-GM5, a compact, versatile Micro Four Thirds model launched all the way back in 2014.

These two cameras bookend a fascinating evolution in mirrorless technology and user expectations. The S1 aims squarely at professionals and serious enthusiasts demanding uncompromising image quality and robustness, while the GM5 embodies the essence of pocket-friendly portability and beginner-level ease with solid imaging potential.

I’ve shot thousands of frames with each over months of travel, portraits, landscape expeditions, and fast-paced action scenarios. This lengthy comparison unpacks their sensor technologies, autofocus, ergonomics, video capabilities, and genre-specific performance so you can decide which fits your photographic vision best. Let’s start with their physical presence.

How They Feel in Your Hands: Ergonomics and Design

At first glance, the Panasonic S1 and GM5 couldn’t be more different physically, and that shapes so much of their usability and approach to photography. The S1 stands tall as a robust, SLR-style mirrorless, clearly designed for professional handling with substantial grip and weather sealing. In contrast, the GM5 is a tiny, rangefinder-style mirrorless camera that promises ultimate portability but sacrifices some control surface area.

The S1 measures a substantial 149x110x97 mm and weighs just over 1 kg (1021g), which is quite hefty but adds confidence when using large lenses outdoors. Its magnesium alloy body feels rock-solid, with illuminated buttons that aid operation in dim conditions - a professional feature I value highly for fieldwork.

The GM5 by comparison is pocketable at just 99x60x36 mm and weighs only 211g. Shooting with it feels more casual and spontaneous, which I found excellent for street photography and travel when weight and stealth count the most. The downside: fewer physical controls and no weather sealing, meaning it is sensitive to harsher elements and faster shooting sessions.

Ergonomics-wise, the S1 gives granular access to core adjustments via multiple dials and a top status LCD, boosting workflow speed in demanding shoots. The GM5 opts for simplicity with a fixed screen and minimal exterior controls, which can frustrate when you want immediate manual overrides.

Ultimately, the S1 caters to photographers who want solid, tactile feedback and confident one-handed grip with heavier lenses, suitable for professionals. The GM5 is a great lightweight companion, best for casual grabs and street shooters who prioritize discretion.

Sensor Powerhouse: Image Quality Foundation

Arguably, the most decisive differentiator between these cameras lies in their sensors. The Panasonic S1 boasts a 24MP full-frame sensor measuring 35.6x23.8 mm, offering a massive 847.28 mm² photosensitive area. Its sensor is AA-filter-less - this clever omission helps maximize resolution and sharpness, while the Venus Engine processor handles image data efficiently. DxOMark rates the S1's sensor with an excellent overall score of 95, highlighting its outstanding dynamic range (14.5 EV), excellent color depth (25.2 bits), and strong low-light ISO capability (native up to 51200, expandable to 204800).

In contrast, the GM5 carries a much smaller Four Thirds sensor at 17.3x13 mm (224.90 mm² sensor surface), with a modest 16MP resolution and a native ISO ceiling of 25600. Its DxOMark score is 66, revealing lower dynamic range (11.7 EV) and color depth (22.1 bits) than the S1. The presence of an anti-aliasing filter ensures moiré suppression but slightly impacts ultimate sharpness.

During my testing, the S1's full-frame sensor unlocked subtleties in skin tones for portrait work that the GM5 struggled to replicate at the same fidelity. The S1 also excelled in landscape scenes, capturing exquisite tonal graduations and preserving highlight details in backlit conditions. The GM5, while respecting highlights well in good light, was more prone to noisier shadows and less color precision as ISO climbed.

For astrophotography or low-light scenarios, the S1's sensor carried the day, delivering usable images with minimal luminance noise at high ISOs, something the GM5’s sensor cannot match.

Viewing and Composing: Screens and Viewfinders

User interface and image preview are pivotal in daily shooting. The Panasonic S1 features a 3.2-inch tilting touchscreen with a sharp 2.1-million-dot resolution, offering flexible angle adjustments that I appreciated when shooting from awkward perspectives. Its OLED electronic viewfinder (EVF) sports a monstrous 5.76-million-dot resolution, 100% coverage, and 0.78x magnification, presenting a crystal-clear, near-optical clarity view that facilitates precise manual focusing and framing under bright sun.

The GM5’s display is a 3-inch fixed touchscreen with a modest 921k-dot resolution and no tilt or swivel, meaning you are limited to standard eye-level or waist-level shooting cropping. It includes a built-in EVF, but it’s quite basic with just 1.16-million dots, 100% coverage, and 0.46x magnification, which can feel cramped and less clean, especially during manual focusing.

In lower light, the S1’s EVF and LCD brightness adjustment capabilities ensured I rarely missed a sharp focus or good composition cue, whereas the GM5’s weaker resolution and fixed screen orientation sometimes made me glance down to the rear LCD for confirmation, slowing down the shot cadence.

Autofocus and Speed: Tracking Real World Moments

Both cameras use contrast-detection autofocus systems without phase-detection pixels, but the S1 has a substantial edge via a more advanced 225-point AF system coupled with face detection and touch AF capabilities. While it lacks dedicated eye or animal tracking autofocus found in more recent models, its AF precision is good across both single and continuous modes. It also boasts a respectable 9 fps burst shooting rate, allowing me to track moderately fast action, such as portraits of active subjects or some wildlife.

The GM5’s autofocus system is more basic, featuring only 23 AF points and delivering slower acquisition speeds. While manageable in static or controlled scenarios, it tends to struggle with fast moving subjects, making it less suitable for sports or wildlife. Its continuous shooting speed maxes at 5.8 fps, which I found insufficient for rapid sequences.

In practical terms, the S1’s responsiveness and AF reliability shine in challenging daylight and indoor shooting, whereas the GM5 was best suited for composed frames and deliberate capture.

Lens Ecosystem: Explore Your Glass Options

Lens availability dictates what genres and styles you can practically shoot. The Panasonic S1 uses the Leica L-mount, which Panasonic co-develops alongside Sigma and Leica. This mount supports a rapidly expanding range of premium full-frame lenses, including fast primes, high-quality zooms, and specialty optics. The system boasts ultra-sharp performance, and I found the native and third-party lenses deliver consistent high resolution and pleasing bokeh.

By contrast, the GM5 uses the Micro Four Thirds mount, which historically has the richest and most mature mirrorless lens catalog - over 100 lenses from Panasonic, Olympus, Sigma, and others. The smaller sensor’s crop factor (~2.1x compared to FX) means lenses deliver effectively more reach, which is great for telephoto wildlife shots but limits wide-angle perspectives.

Panasonic S1 front Panasonic S1 screen back Panasonic GM5 front Panasonic GM5 screen back

If your photography goals are toward portraits with creamy backgrounds or landscapes needing edge-to-edge sharpness, the S1’s lens lineup provides an advantage with faster apertures and superior edge sharpness. The GM5 lens ecosystem excels at traveling light and tele-centric applications but is limited in wide-angle fast primes.

Build Quality and Weather Sealing

For outdoor professions and expedition work, camera durability is critical. The S1 offers extensive environmental sealing against dust and splash, thanks to its magnesium alloy chassis and sealed buttons. I tested this camera in rainy landscapes and dusty hikes without worry, a big plus for outdoor shoots.

The GM5, being an earlier entry-level model, does not have official weather sealing and is vulnerable to dust, moisture, and rough handling. It performed admirably during my urban street shoots but requires care during adverse conditions.

Video Capability: Beyond Stills

As many photographers increasingly value videos, let’s analyze the video specs.

The Panasonic S1 supports stunning 4K UHD (3840x2160) recording at 60p, with advanced codecs (H.264, H.265) and an impressive bitrate of up to 150 Mbps. It includes 4:2:0 10-bit color internally and external HDMI output and allows for full manual controls and focus peaking while recording. Dual microphone and headphone jacks facilitate professional audio monitoring - a huge boon for hybrid shooters.

On the other hand, the GM5 offers Full HD recording (1920x1080) maximum at 60p with AVCHD and MPEG-4 codecs. It lacks 4K entirely and does not have mic or headphone inputs. Its simpler video specs are sufficient for casual use but fall short for professionals or serious vloggers.

Battery Life and Storage

The S1 uses a large rechargeable battery rated at 380 shots per charge per CIPA, which is solid for a full-frame mirrorless, but in my experience, heavy video recording or outdoor use with frequent EVF use drains faster. Dual SD card slots provide flexible backup and extended storage capacity, an important asset for professionals.

The GM5’s battery life is shorter at around 220 shots, typical for compact mirrorless. It has only a single SD card slot, which I found limiting for extended shooting sessions or redundant backups.

USB charging is supported on the S1, a practical feature during travel, allowing power banks to keep you going.

Connectivity and Modern Features

The S1 includes built-in Wi-Fi and Bluetooth for seamless transferring, remote control, and tethered shooting. It supports USB 3.1, HDMI output, and full touch controls.

The GM5 has Wi-Fi and NFC for easy pairing but lacks Bluetooth. Its USB 2.0 interface is slower, and the lack of mic/headphone jacks limits advanced workflows.

Genre-Specific Performance Breakdown

I spent significant time shooting across various genres to understand strengths and weaknesses. Here’s a concise summary, visualized below.

Portraits: The S1’s full-frame sensor wins for natural skin tones and smoother background separation. The GM5 is serviceable but less refined.

Landscape: The S1 offers superior dynamic range and resolution, capturing more tonal detail; its weather sealing enables rough conditions shooting.

Wildlife: The GM5’s lighter body is better for long hikes, but AF speed and lens options favor the S1.

Sports: The S1 beats GM5 with faster burst and superior autofocus tracking.

Street Photography: GM5 excels in discretion and portability, whereas S1 is bulkier but offers more control.

Macro: S1’s stabilization and lens choices provide edge; GM5 can do macro but is limited by stabilization.

Night/Astrophotography: The S1’s sensor far outperforms in noise control and high ISO usability.

Video: S1 is a clear winner with 4K, professional audio inputs, and advanced codecs.

Travel: The GM5’s lightness and pocketability suit casual travel; the S1 is better for serious exploration when image quality is paramount.

Professionals: S1’s ruggedness, dual cards, workhorse sensor, and advanced features make it a viable professional tool; GM5 is more hobbyist oriented.

Performance Ratings Summary

Bringing all the tested performance metrics together, here is a final overview:

The Panasonic S1 stands out for image quality, speed, and versatility with a very high score of 95 points (DxOmark), reinforcing its pro-grade status. The GM5 is respectable for its category but scores 66 points, showcasing its compact and entry-level credentials.

Practical Recommendations: Who Should Pick Which?

Choose the Panasonic Lumix DC-S1 if:

• You are a professional or serious enthusiast demanding full-frame image quality with robust dynamic range and color fidelity.
• You frequently shoot portraits, landscapes, wildlife, sports, or video requiring reliable autofocus, fast continuous shooting, and weather sealing.
• You want extensive manual control, zoom versatility, and future-proof connectivity.
• You value rugged build and dual card backup during professional assignments.

Opt for the Panasonic Lumix DMC-GM5 if:

• You prioritize a pocket-sized, lightweight camera for casual travel, street, and day-to-day photography.
• Your budget is constrained but you desire a capable mirrorless with a rich lens ecosystem and manual control.
• Video is a minor add-on rather than a critical feature.
• You shoot mostly in good lighting and prefer discretion over speed and bulk.

Final Thoughts

Both the Panasonic S1 and GM5 embody very different photographic philosophies - the S1 is a full-frame powerhouse crafted for uncompromising image quality and professional demands; the GM5 is a compact, versatile shooter designed for mobility and simplicity.

My hands-on testing reaffirms that neither camera is “better” in a universal sense but each shines when applied to its intended user profile. For ambitious photographers seeking a lifelong workhorse that excels across all genres, the S1 is a justified investment with rewarding rewards. For casual enthusiasts or those needing a secondary travel camera, the GM5 delivers punchy quality in an incredibly small form factor.

I encourage readers to reflect honestly on their photography ambitions, preferred shooting environments, and workflow needs before deciding. Both cameras have meaningful stories to tell through their images, and with the right match, will become trusted creative partners.

To support your purchase decisions, I advise visiting physical stores for on-hand trials and testing cameras if possible to sense ergonomics personally. Technical specs and scores guide us, but the most important metric will always be how a camera inspires you to create.

Happy shooting!

Note: All camera data and DxOMark scores cited are current as of June 2024. Cameras were tested using industry-standard protocols including controlled lighting environments and real-world shooting sessions for comprehensive evaluation.