Leica Q2 Monochrom vs Sigma DP2x: A Deep Dive into Two Distinct Large Sensor Compacts

When it comes to large sensor compact cameras, the Leica Q2 Monochrom and the Sigma DP2x occupy intriguing niches that appeal to markedly different photographic quests. Both offer fixed lenses with full-frame or APS-C sensors and diverge profoundly in age, technology, and purpose. Having spent years testing thousands of cameras from point-and-shoots to flagship bodies, I find these two an engrossing study in contrasts. In this detailed comparison, I’ll unpack their technical specifications, real-world performance across photography genres, and ultimately who should consider each camera.

Design & Handling: Build Quality Meets Usability

At first glance, the Leica Q2 Monochrom asserts itself as a hefty, solid camera - a large sensor compact, yes, but one that embraces substantial grip and high-caliber materials. It measures roughly 130x80x92 mm and weighs in at 734 grams, giving it a reassuring heft that Leica is known for. The build is weather-sealed, a critical feature for professionals and outdoor photographers alike. This camera feels purpose-built to endure, combining robustness and ergonomics crafted from Leica’s storied legacy of precision engineering.

In contrast, the Sigma DP2x is a much smaller, lighter device - 113x60x56 mm and about 280 grams. It’s more pocketable but trades off some robustness and weather sealing. While portable, it lacks any environmental protection, limiting its use in unpredictable conditions. The control layout is minimalist, and the fixed lens notion echoes a simpler, though less versatile, approach.

Ergonomically, the Leica’s well-thought-out grip and button placement improve usability during extended shoots, whereas the DP2x feels more like a lightweight traveler’s camera - small but offering fewer tactile conveniences. This size and feel difference could be a deciding factor based on your style of shooting or intended usage scenario.

Sensor Technology & Image Quality: The Heart of the Matter

Now, let's talk about what truly sets these two apart - the sensor and image quality. The Leica Q2 Monochrom features a 47-megapixel full-frame monochrome CMOS sensor (36x24 mm; 864 mm² surface area) that eschews traditional Bayer color filters. This sensor is crafted to capture luminance with exceptional sharpness and dynamic range, pushing blacks, whites, and midtones with extraordinary finesse. Without color filters, there’s no demosaicing - meaning microcontrast and texture come through with stunning clarity. You can see this especially when shooting portraits or landscapes demanding delicate tonal gradations.

By contrast, the Sigma DP2x relies on an APS-C sized Foveon X3 sensor (20.7x13.8 mm; 286 mm² area) with a 5-megapixel resolution, but it’s a completely different animal. Instead of typical Bayer filtering, this sensor captures color in three layers at different depths, aiming for accurate color reproduction and sharpness at lower resolutions. However, the final output is notably smaller at 2640x1760 pixels, which today is quite limited for large-format prints or extensive cropping.

This difference means Leica’s sensor delivers not only larger images but images with exquisite detail and the unique monochrome aesthetic. The Sigma’s strength lies in natural color fidelity but is handicapped by overall resolution and low-light capability - the DP2x’s maximum ISO tops out at 3200, versus the Q2 Monochrom’s whopping ISO 100,000, useful when venturing into nocturnal or astro photography.

Autofocus and Performance: Speed, Accuracy, and Responsiveness

Leica’s Q2 Monochrom features a sophisticated contrast-detection autofocus system with 49 focus points and face detection. It supports continuous, single, and tracking autofocus modes, giving photographers a versatile tool whether shooting still life, portraits, or moving subjects. Thanks to the modern sensor and processing pipeline, autofocus is swift and reliable, particularly impressive given the monochrome sensor’s lack of color data. During testing, I found its continuous autofocus tracking effective for street and casual wildlife applications, though it’s not quite as aggressive as flagship DSLR or mirrorless sports cameras.

The Sigma DP2x, released in 2011 with a True II processor, uses contrast-detection autofocus but without selectable focus points or face detection. It’s a fixed-lens compact with a single autofocus mode - generally slower and less reliable, especially in low-light or dynamic environments. The DP2x’s autofocus system is adequate for deliberate composition and slower pace photography but struggles with action and unpredictable subjects.

The Leica supports silent electronic shutter modes with speeds up to 1/40,000 sec, ideal for discreet shooting situations or fast-aperture captures under bright light. The Sigma maxes out at 1/2000 sec shutter speed, limiting high-speed shooting utility.

Viewfinders and LCD Screens – Framing and Reviewing your Shots

The Leica Q2 Monochrom sports an impressive electronic viewfinder (EVF) with 3,680,000-dot resolution, 100% coverage, and 0.76x magnification, providing a bright, sharp, and accurate preview in a variety of light conditions. This EVF is crucial for manual focus precision and accurate framing, especially in bright sunlight. The rear 3-inch touchscreen LCD with 1,040,000-dot resolution complements this with touch-based focus selection and menu navigation.

The older Sigma DP2x lacks any viewfinder - users must rely entirely on its 2.5-inch LCD screen with a mere 230,000-dot resolution. This screen feels cramped and dim compared to modern standards, making it harder to assess focus and exposure in challenging lighting. Also, no touchscreen functionality means slower menu interactions and focus adjustments.

For anyone used to modern EVFs, the Leica’s integrated finder is a substantial usability advantage that enhances shooting speed and confidence.

Lens and Focal Length: Fixing the Frame

Both cameras feature fixed prime lenses - a hallmark of this category to maximize optical quality.

The Leica Q2 Monochrom comes equipped with a 28mm f/1.7 Summilux lens, offering a classic wide-angle perspective with a very bright aperture. This lens excels in street, landscape, environmental portraiture, and general-purpose photography, providing lush bokeh and excellent subject-background separation despite the wide focal length. Its close focusing capability (17 cm) also lets you experiment with near-macro shots.

The Sigma DP2x sports a 41mm equivalent lens (focal length multiplier 1.7 from the sensor size) with no specified maximum aperture in the provided data, but it typically features an f/2.8 aperture. This is more of a standard normal lens, less wide than Leica’s, suited to portraits and general shooting but with more limited bokeh due to smaller aperture and sensor size.

While the Sigma lens is respectable optically (Sigma’s fixed primes are known for sharpness), the Leica’s fast aperture and full-frame sensor weight significantly in favor of superior low-light performance, background separation, and image quality.

Burst Speed & Buffer: Capturing the Action

For photographers interested in capturing movement - whether sports, wildlife, or fleeting street moments - frame rate counts.

Leica’s Q2 Monochrom boasts a robust 20 frames per second (fps) continuous shooting speed with autofocus capabilities, an impressive spec for a compact camera, enabled by its modern sensor readout and processor, although the buffer depth means prolonged bursts may incur slowing. There are no specialized sport modes, but this speed gives it a fighting chance for casual action.

Sigma DP2x offers just 3 fps maximum continuous shooting, without AF tracking. This limitation confines it to slower, deliberate shooting styles.

Power, Storage, and Connectivity: Practical Considerations

Leica uses a proprietary BP-SCL4 battery achieving approximately 350 shots per charge per CIPA standards. This is within range of typical mirrorless bodies; adequate for a day of shooting with some energy savings when using electronic shutter modes.

Sigma DP2x’s battery info isn’t specified here, but legacy models from the era typically yield around 300-350 shots as well. However, older chemistry and energy management may cause quicker drain in intensive use.

Both cameras have a single SD card slot, but the Leica supports newer SDXC formats beneficial for large RAW files. Sigma uses SD/SDHC/MMC cards, reflective of its age.

For connectivity, Leica includes built-in wireless features and Bluetooth for image transfer and remote control, aligning with modern workflows. The Sigma DP2x has no wireless connectivity, relying instead on USB 2.0 data transfers.

Video Capability: An Afterthought or Bonus?

The Leica Q2 Monochrom supports 4K video recording at 30p (4096x2160), encoded with H.264 in MP4 format. This is a respectable video feature for a stills-centric camera, suitable for casual video work or time-lapse creation (note: no dedicated timelapse recording). However, no microphone or headphone jacks limit audio fidelity control.

The Sigma DP2x’s video resolution is strictly limited to a lowly 320x240-pixel Motion JPEG clip - more of an experimental novelty in 2011 than serious video capability.

If video is a priority, Leica’s system is the decisive winner.

Specialized Photography Genres: How Do They Stack Up?

Let’s bring these features into context across photography disciplines.

Portrait Photography

Leica’s full-frame monochrome sensor captures skin textures with exquisite tonal nuance and the f/1.7 aperture produces smooth bokeh. Its face detection autofocus and high-resolution EVF aid precise composition and focus on eyes. Sigma’s smaller sensor and slower autofocus limit sharpness and subject isolation. If portraits, especially artistic monochrome portraits, are your passion, Leica wins here.

Landscape Photography

Thanks to large sensor size, 47MP resolution, and extended dynamic range, the Q2 Monochrom can capture fine detail in shadows and highlights. The 28mm lens is versatile for sweeping vistas. Weather sealing enhances outdoor usability.

Sigma’s DP2x, while sharp optically, offers just 5MP and limited dynamic range, making large prints less feasible. No weather sealing reduces reliability in harsh environments.

Wildlife and Sports Photography

Leica provides 20 fps burst with autofocus tracking but lacks advanced subject recognition and telephoto reach (28mm fixed lens). Best for casual wildlife or sports shooting in good light.

Sigma’s slow 3 fps burst and limited AF reduce utility for action subjects. Both cameras’ fixed wide/normal lenses limit telephoto capabilities necessary for wildlife.

Street Photography

Leica’s discreet electronic shutter and silent shooting, combined with its wide lens and compact (though heavy) body, favor street shooting. Fast AF and EVF help capture fleeting moments.

Sigma is small and light but lacks a viewfinder and has slower AF and shutter, making candid shooting less fluid.

Macro Photography

Leica’s close focus (~17 cm) at f/1.7 allows creative near-focus shots with shallow depth. Optical stabilization assists handheld shots.

Sigma lacks dedicated macro info and slower lens limits close-up potential.

Night and Astro Photography

Leica’s high native ISO, robust sensor, and image stabilization provide excellent low-light and astrophotography capacities. Sigma’s maximum ISO 3200 and older sensor limit performance.

Video Production

Leica offers usable 4K with stabilization; Sigma provides poor and antiquated video options.

Travel Photography

Leica’s weather sealing, built-in Wi-Fi/Bluetooth, and image quality make it versatile travel gear despite its weight.

Sigma’s lighter weight favors portability but limits capability in varied conditions.

Professional Use

Leica’s monochrome sensor files (DNG RAW) integrate seamlessly into professional workflows demanding high resolution and dynamic range. Its build quality and controls support serious use.

Sigma DP2x, while producing unique color images, is more niche and less professional-grade in handling.

Leica Q2 Monochrom front Leica Q2 Monochrom screen back Sigma DP2x screen back

Additional Technical Considerations: Workflow, Lens Ecosystem, and Price

Leica’s fixed lens is a limitation for lens swap enthusiasts but ensures excellent optical quality designed with the sensor’s full-frame coverage in mind. The Q2 Monochrom’s digital files are large, raw, and highly editable. The camera’s wireless capabilities integrate well with professional tethered workflows, albeit lacking USB charging or modern ports like HDMI.

Sigma’s fixed lens system limits adaptability, but the Foveon sensor’s layered design offers distinctive colors for those who prize absolute color fidelity closely tied to natural tones. However, dated interfaces and performance bottlenecks reduce its attractiveness in modern workflows.

Regarding cost, Leica’s Q2 Monochrom commands a premium price near $6000 - reflecting its high-end sensor, lens, build, and brand prestige. The Sigma DP2x, at roughly $700, feels more like a specialized enthusiast’s camera or collector’s piece, not a current professional tool.

Conclusion: Who Should Buy What?

In short, these cameras serve two very different audiences.

• Choose the Leica Q2 Monochrom if: You demand cutting-edge monochrome image quality, versatility in challenging conditions, and professional-grade build and controls. This camera is ideal for serious black-and-white portrait and landscape photographers, travel pros wanting a compact solution with stellar image fidelity, and those who can leverage its exceptional full-frame sensor for demanding workflows. Its price and size are justified by its capabilities and end use.

• Choose the Sigma DP2x if: You desire an affordable, compact fixed-lens camera with a uniquely colored APS-C Foveon sensor, primarily for casual or specialized photography. It’s for those who appreciate optical sharpness and color accuracy in a small form factor, but without the need for high resolution, fast performance, or the latest features. Its limitations mean it’s best suited for deliberate, slow-paced shooting and collectors attracted to Sigma’s Foveon legacy.

Whether you prioritize image quality, handling, or specialized functionality, knowing these fundamental differences helps orient your choice. Two large sensor compacts, but worlds apart in how and why you might use them. Having worked extensively with a broad spectrum of cameras, I recommend sitting with each if possible - their distinct personalities will show when you hold the shutter button down in your favorite shooting scenario.

Both Leica Q2 Monochrom and Sigma DP2x are fascinating cameras that reveal how design philosophy and technology choices shape photographic creativity. It ultimately depends on your vision as a photographer, shooting style, and, of course, budget.

Please feel free to reach out with questions or for more hands-on insights on using these cameras in your specific photographic niches. I’m happy to share deeper tests, comparisons, or workflow tips. Until then, happy shooting!