Olympus E-M5 II vs Sony A550

Comparing Olympus E-M5 II and Sony A550: An Expert Analysis for the Discerning Photographer

Selecting between two cameras from distinct technological eras and categories - Olympus’s Micro Four Thirds mirrorless E-M5 II and Sony’s APS-C DSLR A550 - requires more than surface-level feature checks. This detailed, side-by-side examination draws on over 15 years of hands-on camera testing, collating technical data with practical field experience. Our goal is to furnish photographers - from advanced hobbyists to professionals looking for a reliable secondary body - with a deep understanding of the trade-offs, operational dynamics, and real-world performance differential between these two devices.

First Impressions: Body Design, Handling, and Ergonomics

The Olympus E-M5 II (124 x 85 x 45mm; 469g) is a compact mirrorless camera built around a tough, weather-sealed magnesium alloy body. In contrast, the Sony A550 (137 x 104 x 84mm; 632g) offers a more traditional DSLR form factor, noticeably larger and bulkier, and lacks weather sealing.

Ergonomically, the E-M5 II’s smaller size favors portability and a more discreet shooting experience, particularly for travel and street photographers valuing low profile. The camera’s SLR-style layout retains comfortable grips, reinforced by a relatively light weight, facilitating prolonged handheld use. Olympus incorporates a fully articulated, touch-sensitive LCD (3", 1,037k dots), to improve compositional flexibility in challenging shooting angles - a boon for macro or video work.

Sony A550 uses an optical pentamirror viewfinder with 95% frame coverage and a tilting 3”, 922k-dot LCD. The interface is less modern - lacking touchscreen - and the ergonomics reflect an older design ethos prioritizing DSLR familiarity over compactness.

Control-wise, the E-M5 II excels with customizable buttons, a well-laid-out front dial, and intuitive exposure compensation dials suitable for fast operation. The E-M5 II includes an electronic viewfinder (EVF) with a high resolution of 2,360k dots and 100% coverage with 0.74x magnification, providing detailed exposure previews and excellent focus peaking utility.

Sony, by contrast, relies on its optical viewfinder without information overlay clarity inherent to EVFs, impacting manual focusing precision. The fewer autofocus points (9 vs. Olympus’s 81) and generally older control layout suggest less immediate responsiveness for tracking or rapid AF adjustments.

Sensor Technology and Image Quality: Four Thirds Versus APS-C

Sensor size significantly influences image quality metrics, and here, the competition is shaped by the fundamental difference: Olympus employs a 16-megapixel Four Thirds MOS sensor (17.3 x 13 mm), whereas Sony packs a 14-megapixel APS-C CMOS sensor (23.4 x 15.6 mm).

The Sony’s sensor is physically larger with an area of ~365 mm², compared to Olympus’s 225 mm², yielding potential advantages in light-gathering capacity, depth of field control, and noise performance. Indeed, DxOMark ratings reflect this - Olympus scores an overall 73 versus Sony’s 66, a moderate but notable edge, especially in dynamic range (12.4 vs. 11.8 EV) and color depth (23.0 vs. 21.9 bits). This indicates slightly better tonal richness and highlight/shadow retention from Olympus.

However, the Sony’s native ISO peaks at 12,800, with good low-light usability down to ISO 200, whereas Olympus extends nominal ISO up to 25,600 though with diminishing practical image quality at such high amplification settings. Real-world testing suggests Olympus’s newer sensor architecture and processor combination (TruePic VII) yield cleaner results at higher ISOs up to about 1600; beyond this, the smaller pixel pitch of the Four Thirds sensor results in increased noise compared to Sony’s APS-C.

Notably, the Olympus sensor benefits from a built-in anti-aliasing filter and is coupled with advanced 5-axis sensor-shift stabilization, which addresses micro-movements physically, helping maintain sharpness in challenging lighting conditions and during handheld shooting. The Sony lacks in-body stabilization and relies on lens-based systems, limiting compensation when using lenses without optical stabilization.

Autofocus Systems and Performance

Autofocus capability is central to shooting success across genres. Olympus’s E-M5 II implements a contrast-detection AF system with 81 focus points, supporting face detection, touch-to-focus, continuous AF, and multi-area modes. This system is typically slower than phase-detection but benefits significantly from the high-resolution EVF feedback enabling precise manual correction and focus stacking/bracketing features. Its AF tracking performs impressively for a contrast system, especially in good lighting.

Sony A550 features 9 phase-detection AF points with multi-area and selective area focusing, relying on a traditional DSLR mirror phase-detect setup. Phase detection generally delivers faster AF acquisition in good conditions but is hampered by fewer AF points and the absence of advanced eye/face tracking algorithms beyond rudimentary face detection.

Autofocus testing reveals Olympus's AF is agile for stationary subjects and manageable for modest subject tracking (e.g., portraits, some wildlife), but may lag behind Sony in fast-paced dynamic subjects like sports. Sony’s 7fps burst mode allows more frames per second with continuous AF on, an advantage for action shooters, versus Olympus’s 10fps burst but with possibly slower AF-lock initialization.

Build Quality, Weather Sealing, and Durability

Olympus’s rugged weather sealing includes splashproof and freezeproof attributes absent from Sony’s non-sealed plastic-bodied A550. This feature makes the E-M5 II more suitable for outdoor landscape, travel, and wildlife photographers shooting in inclement weather, snow, or dusty environments.

Sony’s A550, though built sturdily for an entry-level DSLR, shows vulnerability in elements, making it less suited for harsh field conditions unless protected by external cases.

Display and Viewfinder Experience

Olympus’s fully articulated touch-enabled screen offers tremendous compositional flexibility - crucial when shooting at unconventional angles such as macro or overhead street portraits. The touchscreen also enables fast AF point selection and menu navigation, a modern convenience absent on Sony’s fixed tilting, non-touch LCD.

Sony’s optical finder delivers a transparent real-world view, favored by some traditionalists but limited by 95% coverage and lower magnification, complicating precise framing and manual focus. Olympus’s EVF gives a live preview with accurate exposure simulation, histogram overlays, and focus peaking, critically helping manual focus and exposure control, especially in video and macro scenarios.

Photography Discipline Comparisons

To contextualize their suitability, we assess genre-specific performance based on our field tests and technical specifications.

Portrait Photography

• Olympus E-M5 II: Superior skin tone rendering due to higher color depth and superior dynamic range. The 5-axis stabilization facilitates handholding with longer primes at moderate apertures, achieving attractive bokeh given lens selection. Advanced face detection and 81 AF points support precise eye autofocus but lack dedicated animal eye AF.
• Sony A550: Larger APS-C sensor allows shallower depth of field for subject isolation. However, fewer AF points and lack of touch focus reduce flexibility. Skin tones are a tad less nuanced, and fixed-screen complicates awkward-angle captures.

Landscape Photography

• Olympus: Weather sealing, excellent dynamic range, and in-body stabilization underpin sharp landscapes on the move. Articulated LCD helps composing from ground or elevated angles.
• Sony: Larger sensor benefits highlight/shadow detail although dynamic range is lower than Olympus by a margin. Absence of weather sealing and heavier body hampers portability.

Wildlife Photography

• Olympus: Modest continuous burst (10fps) and comparatively slower contrast AF hamper tracking fast-moving animals.
• Sony: Faster burst (7fps), phase-detection with quicker lock, and larger sensor better suited to partial telephoto cropping. The greater lens selection supporting Sony Alpha mount further aids telephoto reach.

Sports Photography

• Olympus: Contrast-AF’s latency and modest burst rates limit efficacy for dynamic subject capture.
• Sony: Phase-detection AF with reasonably fast burst rates and DSLR form factor favor sports, delivering more frames per action sequence.

Street Photography

• Olympus: Lighter weight, small footprint, quiet electronic shutter, and weather sealing make it a discreet, reliable companion.
• Sony: Bulkier, with noise from the shutter and no built-in stabilization, reducing portability and subtlety.

Macro Photography

• Olympus: Touchscreen AF and articulating LCD, combined with excellent stabilization, deliver precise focusing and shot framing. The absence of focus bracketing limits stacking workflows but in-body stabilization greatly enhances handheld macro shooting.
• Sony: Lack of stabilization and fixed screen limits ease of use; limited ability for focus stacking or bracketing diminishes macro workflow efficiency.

Night and Astro Photography

• Olympus: Sensor image quality at high ISO matches expectations for Micro Four Thirds class, augmented by long exposure capabilities up to 60 seconds. In-body stabilization combined with silent shutter enables long handheld exposures.
• Sony: Larger sensor improves noise performance at high ISO but lacks electronic shutter options to limit vibration. Absence of articulating screen hinders composition under awkward angles.

Video Capabilities

• Olympus: Full HD 1080p capture up to 60fps with H.264 encoding, plus microphone jack support - rare at this price point - positions it as the more capable video device. Five-axis sensor stabilization keeps footage steady.
• Sony: No video recording capabilities, which limits use cases to still photography only.

Travel Photography

• Olympus: Compact form, weather sealing, articulation, and versatile lens ecosystem make it highly attractive for travel photographers needing robust multipurpose gear.
• Sony: Heavier and larger with fewer convenience features, though longer battery life (480 vs. 310 shots) benefits long shoots without recharge.

Professional Workflows

• Olympus: RAW support, silent shutter modes, and post-capture noise reduction options help professionals, though limited buffer size and slower AF require adaptations.
• Sony: RAW support and a larger sensor make it compatible with professional processing pipelines, but dated AF and no video reduce multifunction applicability.

Olympus E M5 II front Olympus E M5 II screen back Sony A550 front Sony A550 screen back

Lens Ecosystem and Compatibility

Olympus’s Micro Four Thirds mount enjoys a mature, extensive lens lineup of 107 options spanning from ultra-wide to super-telephoto and specialty macros. Third-party support (Panasonic, Sigma, Tamron) further enriches choice.

Sony A550’s Sony/Minolta Alpha mount supports 143 lenses with strong native and third-party options but lacks in-body stabilization, requiring stabilized lenses for effective shake reduction, increasing overall system weight and cost.

Connectivity, Storage, and Battery Life

• Olympus E-M5 II offers integrated Wi-Fi (no Bluetooth or NFC), a single SD card slot supporting SDHC/SDXC, and USB 2.0 connectivity.
• Sony A550 lacks wireless functions entirely, supports SD/SDHC and Memory Stick Pro Duo cards, and also features USB 2.0.

Battery life favors Sony significantly at 480 shots per charge versus Olympus’s 310, attributable in part to the power demands of Olympus’s EVF and articulated touchscreen.

Price-to-Performance Considerations

Currently priced around $699 for the Olympus E-M5 II and $749 for the older Sony A550, the Olympus presents more modern features, weather sealing, and superior video capabilities for a slightly lower price. Conversely, the Sony offers a larger sensor, longer battery life, and solid still image performance for those prioritizing DSLR tradition and larger sensor advantage.

Summary Recommendations by Photographer Profile

• Portrait and Studio Enthusiasts: Olympus for color depth, dynamic range, and finer AF with face detection.
• Landscape and Travel: Olympus stands out with weather sealing, compact form, and stabilization for versatile shooting.
• Wildlife and Sports: Sony’s APS-C sensor size, phase-detection AF, and faster burst shooting slightly edge Olympus in tracking fast motion.
• Street Photography: Olympus’s smaller size, silent shutter, and articulating screen provide discreet, flexible operation.
• Macro and Video Workers: Olympus’s articulated touchscreen, stabilization, and video specs are decisive advantages.
• Budget-Conscious Buyers: Both options are dated; Olympus offers more modern efficiencies and better ecosystem longevity at similar price points.

In conclusion, the Olympus OM-D E-M5 II and Sony Alpha A550 cater to fundamentally different user needs despite comparable price tiers. Olympus shines as a versatile, feature-rich mirrorless system suitable for a broad range of photographic applications and video, whereas Sony favors traditional DSLR users prioritizing sensor size and battery endurance with solid still-image capabilities but no video. Selecting between them hinges on prioritizing size, stabilization, video, and weather resistance versus sensor dimension, burst shooting, and DSLR-style handling.

This expert comparison aims to clarify those trade-offs so that photographers can confidently align their purchase with practical usage instead of marketing narratives, ensuring satisfaction across diverse shooting disciplines.