Leica SL2-S versus OM System OM-1: A Hands-On Expert Comparison for Serious Photographers

When two pro-grade mirrorless cameras from prestigious brands face off, the discussion is often about more than specs - it involves legacy, system compatibility, and their real-world behavior in your hands. Today, I’ll share my detailed, 2500-word comparison of the Leica SL2-S and the OM System OM-1. Both claim professional credentials, but they come from very different design philosophies, sensor technologies, and ecosystem strategies.

Having spent weeks testing these two cameras across multiple genres - from wildlife in the wild to studio portraits and nightscapes - I want to take you through a comprehensive, experience-rich dive. We’ll unpack key technical aspects, handling and ergonomics, autofocus behavior, image quality, video capabilities, and more, ending with well-rounded recommendations tailored to specific photographer profiles.

Let’s get started.

First Impressions: The Build and Ergonomics Face-Off

Leica and Olympus (now OM System) both produce mirrorless cameras with SLR-style bodies - built for professional use - but their approaches vary substantially.

The Leica SL2-S is a large, robust machine built from solid magnesium alloy. It weighs 931 grams and measures 146x107x83 mm. At first touch, it exudes a confident heft that conveys durability and precision engineering; you instantly feel you’re working with a camera designed for long endurance and serious handling.

In contrast, the OM System OM-1 is significantly more compact and lighter at 599 grams and 135x92x73 mm - a very noticeable difference when you’re carrying gear all day. The OM-1 carves out impressive weather-resistant sealing in a smaller footprint, making it feel nimble without feeling fragile.

Ergonomically, the Leica goes for simplicity and tradition, with a fixed 3.2-inch touchscreen and minimal extraneous buttons. The OM-1 features a fully articulated 3.0-inch screen that’s touchscreen-enabled and oriented toward versatility, including selfie-friendly use.

I found the Leica’s heft reassuring on extended shoots - especially outdoors in cooler weather, where gloves are necessary. The OM-1’s smaller size makes it ideal for street shooting or travel when you want to minimize fatigue without sacrificing pro features.

The top control layouts also hint at their priorities: the Leica emphasizes clean classic ergonomics with subtly placed dials and no illuminated buttons, while the OM-1 provides a more densely packed control set.

Sensor Technologies: Full-Frame vs. Stacked Four Thirds

One of the most fundamental differences lies in the sensor systems. The Leica SL2-S sports a full-frame 24MP CMOS sensor (36x24mm), while the OM System OM-1 offers a 20MP stacked BSI Live MOS sensor sized 17.4x13mm (Four Thirds format) with a 2.1x crop factor.

Both sensors omit the optical low-pass filter to maximize resolution and sharpness but serve very different creative and technical markets.

From a raw resolution standpoint, Leica’s full-frame sensor outputs 6000 x 4000-pixel images benefiting from larger pixel pitch and theoretically superior dynamic range and low-light capabilities. In my side-by-side ISO tests, the Leica’s sensor handles noise gracefully up to ISO 50000 boost, though practical sweet spots are closer to ISO 12800 for clean results.

The OM-1’s stacked sensor is a technological marvel, delivering faster readout speeds, better electronic shutter performance, and impressive ISO range extending up to a 102400 boost. In real use, its low-light noise is surprisingly well controlled for a smaller sensor, thanks largely to new BSI and processing advances.

However, the smaller sensor does not match the per-pixel clarity and dynamic range latitude offered by Leica’s chip. Landscapes with complex shadows and highlights typically exhibit more gradations and subtle tonality with the SL2-S’s sensor.

The OM-1’s sensor, paired with its Micro Four Thirds lens ecosystem, offers tremendous telephoto versatility (more on this below), and excellent autofocus performance, especially when factoring in its animal eye detection AF.

Autofocus and Tracking: Precision in Action

Autofocus is often a dealbreaker, especially for wildlife and sports photographers.

The Leica SL2-S incorporates 225 contrast-detection AF points with advanced face detection but lacks phase-detection technology, which is somewhat unusual for a pro body launched in 2020. The system is reliable in good light, precise with face and eye detection, but can struggle tracking fast-moving subjects in challenging environments. It works well for portraits and static subjects, but less so for birds in flight or erratic sports action.

Conversely, the OM System OM-1 features a hunting pack of 1053 hybrid AF points (contrast and phase detection), taking autofocus to the next level. It includes advanced subject recognition - human and, notably, animal eye AF - a boon for wildlife and pet shooters. In burst mode at 10fps, the OM-1 maintains remarkable locking on subjects with complex movement.

The OM-1’s focusing system notably outperformed the SL2-S in low light and high-movement scenarios during my field tests, where I tracked falcon flights and fast-moving runners with confidence.

Continuous Shooting and Buffering

Speed matters when shooting action.

The SL2-S offers a blistering 20fps burst with the electronic shutter (silent mode), doubling most professional full-frame mirrorless cameras. That said, the buffer fills relatively quickly when shooting RAW+JPEG, so managing card speeds and buffer clearing is necessary for long shoots.

The OM-1 offers a more modest 10fps burst rate, still respectable, especially for its class and size. Thanks to its stacked sensor and processor, it maintains consistent AF tracking during continuous shooting without noticeable lag.

While the Leica leads on raw speed, the OM-1’s combination of tracking stability and burst creates an effective weapon for sports and wildlife under most circumstances.

Image Stabilization: Sensor-Based Solutions

Both cameras have in-body image stabilization (IBIS) - a critical feature for telephoto, macro, and low-light shooting.

The Leica SL2-S uses sensor-shift stabilization, but Olympus pioneered some of the best IBIS tech, and the OM-1’s 5-axis sensor-based stabilization is considered among the top performers on the market. Olympus’s system compensates up to 7.5 stops with compatible lenses, an impressive feat that can sometimes rival tripod levels of steadiness.

This difference becomes particularly noticeable when shooting handheld telephoto or macro, where subtle shakes can ruin images.

Build Quality and Environmental Durability

Both cameras offer professional-grade weather sealing, designed to resist dust and moisture ingress but are not waterproof.

Leica’s body feels slightly more rugged and premium with its cold hammersmith finish and robust chassis. The OM-1’s sealing is solid too, with resistance to cold down to -10°C and splash-proof construction.

If your work routinely places you in extreme environments or wet weather, both will hold up, with a slight edge to Leica’s reassurance in heavy-duty use.

LCD and Viewfinder Experience

Good LCDs and viewfinders are critical for composition and reviewing images in varied conditions.

The SL2-S sports a fixed, 3.2-inch 2100k-dot touchscreen. It’s sharp, responsive, but the fixed angle can limit creativity when shooting low or high angles.

The OM-1’s 3.0-inch screen is fully articulated and also touch-sensitive, allowing flexible positioning - a feature I appreciated when shooting macro and video.

Both share impressive 5.76M-dot OLED electronic viewfinders covering 100% frame with high magnification (0.78x Leica, 0.83x OM-1). The display clarity and refresh rates are excellent on both, minimizing lag and motion blur.

Lens Ecosystems and Compatibility

Let’s talk glass. The Leica SL2-S uses the proprietary Leica L mount, supporting 36 native lenses ranging from ultra-sharp primes to pro zooms. Leica glass is known for its incredible micro-contrast, skin tone rendition, and solid build quality, though lenses tend to be pricey.

The OM System OM-1 relies on the far more extensive Micro Four Thirds mount, boasting a staggering 118 lens options from Olympus, Panasonic, Sigma, and third-party manufacturers. This opens vast creative possibilities, especially in telephoto and macro, with more affordable high-performing options.

The 2.1x crop factor on OM-1 lenses means a 300mm MFT lens behaves like a 630mm on the Leica full-frame sensor in terms of field of view - a big advantage for wildlife and sports photographers needing reach without huge, heavy lenses.

Video Capabilities in Practice

Both cameras offer solid video features tailored for professional creators.

The Leica SL2-S delivers UHD 4K video at up to 60p with a high bitrate nearing 400 Mbps in MOV/H.264 format, plus full-frame sensor readout for shallow depth aesthetic. It also supports full HD 120fps slow-motion, headphone and microphone ports, and USB 3.2 for fast tethered workflows.

The OM-1 records 4K UHD at up to 60p in multiple codecs, including efficient H.265/HEVC alongside H.264. Its fully articulated screen and smaller size make it handy for run-and-gun shooting. Olympus’s legendary IBIS also shines in video stabilizing.

Both provide time-lapse recording and customizable exposure modes for night or astrophotography timelapses.

Battery Life and Storage Insights

Battery life is similar, with Leica’s SL2-S rated for roughly 510 shots whereas OM-1 offers about 520 shots per charged battery. Both use proprietary lithium-ion packs and dual SD card slots supporting UHS-II speeds.

The OM-1’s lighter battery and body combo suits travel and street setups nicely, while the Leica’s battery complies with heavier duty usage.

Hands-On Genre Insights: Who Shines Where?

To bring the data to life, I tested these two cameras across several major photography disciplines, comparing results and usability to identify the best fit by user needs.

Portraits: Skin Tones, Bokeh, and Eye Detection

With full-frame sensor advantages, the Leica SL2-S produces creamy, natural skin tones and beautiful gradations with a distinct three-dimensional quality in portraits. Its lack of phase-detect AF leads to slightly slower eye detection, but overall accuracy is excellent in good light.

OM-1’s smaller sensor results in deeper depth-of-field at identical apertures, meaning bokeh is less dreamy but still very usable. Thanks to its advanced face and animal eye AF, the OM-1 tracks eyes quickly and reliably, even in challenging light.

Verdict: For classic portraiture, Leica wins on image quality and tonal rendition; OM-1 offers a very competent alternative with faster AF.

Landscape Photography: Dynamic Range and Weather Sealing

Leica's 24MP sensor offers superior dynamic range, capturing extended shadow and highlight detail with more room to maneuver in post. Full-frame advantages and Leica’s excellent glass give landscape photographers rich files.

The OM-1’s stacked sensor keeps pace in color fidelity and shadow recovery, though its Four Thirds sensor physically captures less light. The camera’s smaller size and articulation give practical shooting advantages on location.

Both handle weather-facing conditions equally well.

Verdict: Leica’s sensor ultimately delivers superior high-res, wide-dynamic-range images; OM-1 trades some quality for versatility and portability.

Wildlife Photography: Autofocus and Telephoto Reach

Here, the OM System OM-1 clearly excels due to its hybrid AF with over 1000 points, advanced animal eye detection, and inherent 2.1x crop factor extending telephoto reach without added lens weight or size.

The Leica achieves excellent image quality and rapid shooting speeds but lacks comparable AF sophistication and reach unless paired with bulky telephoto Laowa or Leica zooms, which are a heavy load.

Verdict: OM-1 is the clear winner for wildlife and bird photography thanks to AF intelligence and native telephoto advantage.

Sports Photography: Tracking, Frame Rate, and Low Light

The super-fast 20fps burst on the Leica is attractive for freezing peak action moments. The SL2-S holds up well in sports arenas with its high ISO performance and accurate face/eye detection but is limited by contrast-only AF for tracking.

OM-1’s 10fps is slower but offers superior subject tracking with hybrid phase detection and animal eye AF - useful for motorsports and unpredictable athlete movements.

Verdict: Leica offers better raw speed for sequential shooting, OM-1 delivers smarter focusing for complex subjects.

Street Photography: Discretion and Portability

The OM-1 punches above its weight class for candid, street setups thanks to its much smaller size, lighter weight, and silent electronic shutter capabilities up to 1/32000s.

Leica’s size and weight make it more conspicuous but rewarded with masterful ergonomics and gorgeous files.

Verdict: OM-1 is more discreet and suitable for a nimble street shooter; Leica caters to those prioritizing image quality and handling.

Macro Photography: Precision and Stabilization

The OM-1’s superior 5-axis IBIS combined with an extensive MFT macro lens selection (many stabilized) makes close-up shooting easier and more forgiving handheld.

The Leica’s stabilization is good but less refined, and lens choice for macro is more limited and expensive.

Verdict: OM-1 is friendlier for macro enthusiasts looking for handheld flexibility.

Night and Astrophotography: High ISO and Exposure Modes

Leica’s full-frame sensor leads with better noise control and cleaner shadows at high ISO values and long exposures, coupled with manual mode controls.

OM-1 offers boosted ISOs up to 102400 and excellent processing but exhibits more noise, typical for sensor size.

Both cameras offer timelapse and interval exposure modes, though the OM-1’s articulating screen aids night composition.

Verdict: Leica is preferred for clean astrophotography, OM-1 manages well for general night shoots.

Video Use: Resolution and Stabilization

Both cameras support UHD 4K at 60p, full HD 120fps, and have microphone/headphone jacks for professional audio control.

OM-1 provides HEVC video codec support for efficient editing file sizes and superior IBIS for handheld video.

Leica offers higher bitrate options optimizing quality for color grading workflows.

Verdict: Leica excels in pure video quality; OM-1 is more versatile for run-and-gun shooters.

Travel and Everyday Use: Battery and Weight Considerations

OM-1’s compact size and identical battery life to Leica’s, along with advanced weather sealing, better suit frequent travelers and street photographers prioritizing mobility.

Leica offers durability and ergonomics that shine during extended shoots or studio to field transitions.

Professional Workflow: File Formats and Reliability

Both cameras support lossless RAW output and dual card slots for secure shooting.

Leica uses proprietary image processing tuned for skin tones and detail; files integrate well with professional editing suites.

OM-1 benefits from new processor speed, supporting focus stacking and bracketing natively - valuable in professional compositional workflows.

The Final Scores – Summarized

While you can't buy a perfect camera, here’s a solid summary of how they perform across key factors:

And broken down by major photography genres:

Which Camera Should You Buy?

• Choose the Leica SL2-S if you prioritize best-in-class full-frame image quality, portrait and landscape work, robust handling, and solid video bitrate for cinematic projects. It’s best suited to photographers who already invest in Leica glass or want a premium system to carry long-term.

• Choose the OM System OM-1 if you want a more affordable, lightweight, versatile package with industry-leading autofocus, excellent IBIS, and a massive lens ecosystem. It’s ideal for wildlife, sports, macro, street photography, and travel thanks to its portability and autofocus sophistication.

Both cameras offer dual card slots, robust weather sealing, and full professional controls. Your choice should weigh sensor size vs. lens ecosystem, autofocus demands, and ergonomic preferences.

Final Thoughts

The Leica SL2-S and OM System OM-1 represent two distinct professional mirrorless philosophies with impressive features, steady performance, and loyal user communities. In my extensive hands-on experience, they both delivered value tailored to different photographic workflows and budgets.

If your work demands impeccable full-frame quality and you value Leica’s minimalist control sophistication, the SL2-S remains a compelling option despite its hefty price tag.

If you’re seeking cutting-edge autofocus, stabilization, and a compact system with tremendous reach and flexibility, the OM-1 stands tall as a modern, versatile powerhouse.

Both cameras uphold reliability and professional integrity, so your choice really boils down to personal style, subject preferences, and investment scope. Either way, you’re getting an expert-grade tool that supports expansive creativity.

Thank you for joining me on this comprehensive comparison. I hope this analysis empowers your next camera decision with deeper insight cultivated through numerous field hours and critical evaluation.

Feel free to ask any questions or share your experiences with these cameras - I’m always eager to continue the conversation!

Article and all images © 2024 by [Your Name], Camera Equipment Reviewer and Photographer.