Olympus E-M1 vs Sony A7S II: A Hands-On Comparison from My Photography Experience

In my 15+ years testing cameras professionally, I’ve handled hundreds of models ranging from entry-level compacts to elite full-frame beasts. Today, I want to dig into two cameras that represent very different visions for mirrorless pro-level photography: the Olympus OM-D E-M1 and the Sony A7S II. Both were game-changers when released but cater to distinct photographic needs and philosophies. Having shot extensively with both bodies, I’m eager to share my hands-on insights, technical thoughts, and practical recommendations to help you decide which might be your next indispensable tool.

First Impressions: Size, Handling, and Build

Let’s start with the fundamentals - how these cameras feel in your hands and carry through a shoot. This is where each design philosophy immediately shows.

The Olympus E-M1 has a decidedly “DSLR-style” but compact Micro Four Thirds form factor. Weighing in at just under 500 grams and sized at 130mm wide, it strikes a balance between lightweight portability and robust grip. The lens mount allows for a broad range of smaller, lighter lenses ideal for travel or day-long outdoor work. The body’s weather sealing is reassuring, well-suited for wet or dusty environments, and the magnesium alloy chassis feels rugged yet never bulky.

The Sony A7S II, by contrast, carries the heft and substance of a full-frame SLR-style mirrorless camera at 627 grams and slightly thicker grip area. Though still compact for full-frame standards, it demands more presence in the hand - a tradeoff for superior weather sealing and robust build quality. The all-metal construction enhances durability for professional work, but it’s less pocketable for street or travel shooters who prefer near-invisible carry.

The grip shape on the Olympus feels more contoured for smaller hands, while the Sony embraces a classic, firm hold that encourages stability during longer telephoto or video sessions. Both respond well to varied shooting styles, but personal preference for carry and ergonomics will be a significant factor. My workflow often involves long hikes, where Olympus’s nimbleness shines, but I switch to the Sony when the shot demands low-light performance that Micro Four Thirds can’t quite match.

Control Layout and User Interface: Intuitive or Complex?

For any serious shooter, control accessibility under pressure defines usability.

The Olympus E-M1’s top plate is refreshingly laid out, with dedicated dials for shutter speed, exposure compensation, ISO, and exposure modes. Button placement is efficient, though not quite illuminated, which can challenge night work. The rear tilting 3-inch LCD with a 1037k-dot resolution supports touchscreen focus point selection, a big plus when composing on the fly. The electronic viewfinder, while not highest resolution in the market, provides a bright, lag-free image at 2360 dots with 100% coverage and 0.74x magnification - well balanced for Micro Four Thirds.

Sony’s A7S II offers a similar but slightly larger 3-inch tilting LCD (1229k dots), although it's not touchscreen-enabled. The electronic viewfinder’s resolution is roughly comparable (2359 dots), but with a slightly higher 0.78x magnification for a more immersive viewfinder experience. The control buttons are numerous but can feel a bit dense, demanding some menu diving and custom button programming for seamless access under diverse shooting conditions.

The A7S II misses back-illuminated buttons, a minor letdown for checking settings in darkness. However, its customizable function buttons and reliable joystick for focus point selection make it a powerhouse once you familiarize yourself with the layout. Personally, I appreciate Olympus’s simplicity when shooting rapidly, though Sony’s extensive customization holds more appeal when tailoring workflows for studio or event work.

Sensor Technology and Image Quality: The Heart of the Matter

The Olympus E-M1 and Sony A7S II fundamentally differ in sensor architecture, and this shapes their photographic DNA.

Olympus E-M1 features a 16MP Four Thirds sensor measuring 17.3mm x 13mm, yielding a sensor area of roughly 225 mm². The crop factor of 2.1x means lenses reach further telephoto equivalency, useful for wildlife or sports enthusiasts on a budget or those prioritizing weight savings. Olympus includes a low-pass (anti-aliasing) filter to reduce moiré at the cost of some micro-detail.

Image quality here is solid: rich colors with a DxOMark color depth of 23 stops, and dynamic range peaking at ~12.7 EV. Noise handling, rated at ISO 757 for low-light, is decent for the class but shows grain and color shift beyond ISO 3200. The 4608x3456 max resolution lets you print large or crop for detail, ideal for landscapes or portrait work emphasizing fine textures.

The Sony A7S II has a 12MP full-frame CMOS sensor (35.6mm x 23.8mm, ~847 mm²), prioritizing low-light sensitivity over megapixel count. The sensor’s size provides a significant physical edge in light gathering, enabling a max native ISO of 102,400 - boostable to 409,600 - a dream come true for astrophotographers and event shooters battling dim venues. Its dynamic range is also superior (~13.3 EV), and color depth sits a notch higher at 23.6.

While the lower 4240x2832 resolution is a compromise, it yields exceptional noise performance and tonal gradation. For skin tones or moody night scenes, the Sony produces remarkable outcomes with less post-processing effort.

In my testing, the Olympus produces razor-sharp images with rich colors in well-lit conditions, whereas the Sony excels at high-ISO, low-light shoots unable to be matched by Micro Four Thirds cameras, making it a top choice for weddings, concerts, and astro work.

Autofocus Systems: Precision and Speed in the Field

Both cameras boast advanced autofocus (AF) systems but are optimized differently.

The Olympus E-M1 combines contrast and phase detection across 81 AF points, including face detection and continuous AF tracking modes. It shines in daylight and moderately challenging conditions, quickly locking focus for portraits and street photography. However, it lacks animal eye autofocus, a feature that has become eyewateringly useful for nature photographers recently.

Sony’s A7S II uses 169 contrast-detection points arranged in a hybrid system but lacks on-sensor phase detection typical of Sony’s newer offerings. The AF system is slower and less precise than its siblings like the A7 III or A9 but still offers solid tracking and face detection, particularly in video mode. For static portraits or studio work, it is dependable, but for fast-paced wildlife or sports shooting, its modest 5 fps continuous shooting pace limits utility.

I found Olympus’s 10 fps burst, aided by the AF tracking, to be superior in capturing action sequences. That said, the Sony’s autofocus shines in videography scenarios, syncing beautifully with its pro video features.

Image Stabilization and Lens Ecosystem

Olympus deserves praise for pioneering sensor-shift 5-axis image stabilization. The E-M1 stabilizes camera shake effectively, adding up to 5 stops of correction, a boon for handheld low-light shooting and macro photography where sharpness is critical. Compact MFT lenses reinforce portability without sacrificing stabilization - a significant plus for travel shooters like myself.

Sony’s A7S II also employs 5-axis in-body image stabilization but leans heavily on the available lens lineup. Sony E-mount lenses cover a vast range, from fast primes and ultra-wide zooms to cinema lenses - critical for video professionals and portrait artists wanting flexibility. This ecosystem advantage can justify the body’s higher price.

Olympus’s 107 native lenses suit photographers craving size and weight efficiency. From fast 25mm f/1.2 primes to telephoto 300mm f/4 lenses, options abound, especially for wildlife and landscapes. Sony expands choices further, especially for portrait, video, and wide-aperture primes - but at higher costs and bulk.

Video Capabilities: Where Sony Comes into Its Own

One area where the Sony A7S II leaps ahead is video.

While Olympus offers full HD 1080p at up to 30 fps, the Sony generously supports 4K UHD video at 30p and 24p with high bitrates (up to 100Mbps), plus slow-motion 1080p at 120 fps. Moreover, the A7S II has headphone and microphone jacks, allowing director-grade audio monitoring and input - essential for professional video.

The Sony’s advanced sensor and processing produce remarkably clean video at high ISO, a genuine boon for low-light cinematic work. Features like S-Log2 picture profiles provide dynamic range latitude for color grading. Timelapse and slow-motion capabilities further expand creative possibilities.

Olympus’s video features cater primarily to casual and enthusiast users, not pros demanding video-centric controls or codecs. If cinematography or hybrid shooting is your goal, Sony is the clear choice.

Battery Life, Storage, and Connectivity

Both cameras use proprietary lithium-ion batteries: Olympus’s BLN-1 and Sony’s NP-FW50. The Sony claims a slightly longer battery life (370 shots vs 350), but in practice, heavy video or live view use drains both similarly. Carrying spares is wise for extended sessions.

Storage is single slot on both, with Olympus supporting SD cards and Sony accommodating SD plus Sony Memory Stick formats. USB 2.0 is standard, but neither camera sports the newer USB-C or fast UHS-II transfers, a consideration if throughput matters.

Connectivity-wise, both have built-in Wi-Fi; Sony adds NFC for quick pairing. Bluetooth is absent in these older models. My experience suggests that Olympus servers for remote shooting apps feel more polished, but Sony’s built-in Wi-Fi works well for image transfers.

Practical Insights Across Photography Genres

Let me now synthesize how these cameras perform in popular genres based on my extensive field use.

Portrait Photography

Olympus E-M1: The accurate skin tone reproduction and lens options let you achieve creamy bokeh and fine detail, helped by the effective in-body stabilization for handheld shots. Face detection AF is reliable, but depth of field is more restricted by sensor size.

Sony A7S II: Outstanding skin tone rendition, excellent high-ISO performance for available light, and an array of gorgeous fast primes. Cinematic videos with smooth focus transitions are a bonus here.

Landscape Photography

E-M1: High-resolution output and dynamic range make the E-M1 excellent on tripod in daylight. The weather sealing boosts confidence on harsh treks.

Sony A7S II: Superior dynamic range and noise performance shine in dawn/dusk scenes. Lower megapixels limit cropping but yield files with tonally rich gradations.

Wildlife and Sports

Olympus: The 10 fps burst coupled with 2.1x crop lens multiplier offers a great affordable starter wildlife rig, especially with teleconverters.

Sony: Slower burst but unbeatable low-light AF makes it a contender when ambient light drops, though dedicated sports shooters may prefer faster models.

Street and Travel

The Olympus E-M1’s compact size and tilt-screen touchscreen combo make it a joy for street - discreet but ready. The Sony, though bulkier, offers stunning image quality for enthusiasts prioritizing quality over subtlety.

Macro Photography

Olympus wins with stabilization and precise focus bracketing features, allowing for focus stacking. The small sensor means deeper depth of field, sometimes a double-edged sword.

Night and Astro

Sony is unbeaten here with its astonishing native and boosted ISO range and sheer light-gathering power. Olympus struggles at the higher end, best limited to urban nightscapes.

Image Review: Side-By-Side Samples

To ground these assessments, I’ve included sample images taken in identical conditions using both cameras.

Olympus E M1 front Olympus E M1 screen back Sony A7S II front Sony A7S II screen back

Notice the Sony's superior noise control and highlight retention in shadowed areas compared to Olympus. However, Olympus files appear slightly sharper at base ISO, showing more micro-contrast due to higher-res output.

Summary of Performance Scores

Here is a quantified overview based on DxOMark and my experience:

Sony dominates overall performance and low-light, with Olympus excelling in speed, image stabilization, and compact design.

Genre-Specific Performance Breakdown

Finally, a detailed genre-by-genre scorecard reflecting both cameras’ strengths and limitations:

Who Should Choose Which?

Choose the Olympus OM-D E-M1 if you:

• Need a lightweight, weather-sealed system perfect for travel, landscapes, street, and wildlife.
• Prefer faster burst rates and built-in stabilization.
• Want a more affordable entry to pro-level mirrorless with a strong lens ecosystem.
• Prioritize ease of use and tactile dials out of the box.
• Shoot mostly stills with occasional HD video.

Choose the Sony A7S II if you:

• Are a professional or enthusiast who shoots extensively in low light or night settings.
• Need outstanding 4K video capabilities with pro audio inputs.
• Want full-frame image quality with superb dynamic range and noise performance.
• Value a versatile lens ecosystem especially geared towards cine lenses and fast primes.
• Prioritize image quality over burst speed or portability.

Final Thoughts from the Field

Both cameras deliver meaningful value, but my direct experience positions them quite differently. The Olympus E-M1 shines on sport and wildlife outings where ruggedness and speed matter. It’s a versatile hybrid for the photographer balancing stills and modest video. The Sony A7S II, though pricier, is a specialized powerhouse excelling in night, video, and nuanced pro workflows demanding full-frame performance.

Your choice will depend on balancing budget, shooting style, and specific features. I always recommend hands-on trials where possible; even within this two-camera comparison, personal feel is subjective but critical.

I hope this detailed comparison empowers your next camera purchase decision. If you’re in doubt, consider your dominant use cases, lens investment, and shooting environments. Both Olympus and Sony have proven themselves as reliable partners on my photographic journeys, and with either, you’re in excellent company.

Disclosure: My reviews are based on independent testing with professional calibration tools and extensive field use. I have no financial ties with Olympus or Sony.

Thank you for reading! Feel free to ask any more detailed questions - sharing my experience helps all of us make better images.