• 4/3 224.9mm2
  • 16.1 megapixels
  • ISO 200 - 25,600
  • 35mm 847.3mm2
  • 12.2 megapixels
  • ISO 100 - 102,400

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Differences

Olympus E-M1 advantages over Sony A7S

  • Lens selection
    Excellent vs Good
    Better lens selection gives you more options
  • Less expensive
    $1099 vs $1998
    Save money for lenses or accessories
  • In-Camera Image Stabilization
    Yes vs No
    Reduces the effects of camera shake at slower shutter speeds
  • Touchscreen
    Touch vs No touch
    Interact with your camera just like your smartphone
  • Fast startup
    ~0.80 vs 2.0 sec
    Faster startup lets you catch the moment
  • On-sensor phase detect
    Yes vs No
    Usually improves live view and video AF performance
  • More pixels
    16.1 vs 12.2 megapixels
    Higher resolution photos
  • Lacks anti-aliasing filter
    No Filter vs Filter
    Enjoy sharper photos
  • Longer exposure
    60 vs 30 sec
    Long exposures for night shots
  • Faster JPEG shooting
    9.9 fps vs 5.0 fps
    Faster JPEG shooting (burst mode)
  • Faster RAW shooting
    9.9 fps vs 5.0 fps
    Faster RAW shooting in burst mode
  • Faster shutter
    1/16000 vs 1/8000 sec
    Shoot wide open in bright light

Sony A7S advantages over Olympus E-M1

  • Larger sensor
    35mm vs 4/3
    More sensor area. Bigger is (generally) better.
  • Bigger pixels
    ~ 8.40 vs 3.75 microns
    Better low-light and dynamic range (all else equal)
  • In-camera panoramas
    Yes vs No
    Stitches multiple shots into a panoramic photo
  • NFC
    Yes vs No
    Simplifies pairing your camera with supported phones
  • Higher effective ISO
    3,702 vs 757 iso
    Take photos in low light with less noise
  • Thinner
    48 mm vs 63 mm
    Thinner
  • Shoots 24p video
    Yes vs No
    Gives your movies a big-screen feel
  • Shoots 60p video
    Yes vs No
    A faster framerate can give you more editing options
  • Headphone jack
    Yes vs No
    Monitor audio recording while you shoot video
  • Has anti-aliasing filter
    Filter vs No Filter
    Reduces unsightly moiré in photos
  • Slow-motion videos
    Yes vs No
    Shoot slow-motion videos
  • Higher extended ISO
    409600 vs 25600 ISO
    Higher extended ISO can give more low-light flexibility

Similarities

Common Strengths

  • Focus peaking
    Both provide
    Your camera will highlight what's in focus
  • Eye-level viewfinder
    Both provide
    You'll be able to frame photos even when the sun is out
  • Tiltable Screen
    Both provide
    Tilt the screen for shooting flexbility
  • Built-in Wi-Fi
    Both provide
    Share your photos wirelessly
  • External Mic Jack
    Both provide
    Improved sound fidelity when shooting video
  • HDMI out
    Both provide
    Use HDMI output to monitor or review video
  • Hot shoe
    Both provide
    Off-camera flashes open new possibilities
  • Bulb shutter
    Both provide
    Hold the shutter open manually for long exposures

Common Weaknesses

  • Tilt-swivel screen
    Neither provide
    Tilt and swivel the screen for maximum shooting flexibility
  • Built-in Bluetooth
    Neither provide
    Always-on wireless connectivity
  • Built-in GPS
    Neither provide
    Geotag your photos
  • Internal flash
    Neither provide
    Useful in a pinch for fill flash
  • Top deck display
    Neither provide
    Check settings with a screen on top of the camera
  • Dual card slots
    Neither provide
    Gives you more storage flexibility

User reviews

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Review Excerpt

  • Exceptional rugged, weather-proof, professional build; Lightning fast contrast-detect AF, and phase-detect AF that makes Four Thirds lenses far more responsive; Tons of useful physical controls with immense customizability; Arguably the best image quality of any Micro Four Thirds camera we've tested to date; Large, sharp, high-resolution electronic viewfinder; Advanced Wi-Fi capabilities, including remote control shooting in PASM exposure modes.

  • Bigger and heavier than many other compact system cameras; Most expensive Micro Four Thirds camera on the market to date; Menu system and customization options have a steep learning curve; No optical low-pass filter means greater risk of moire; No built-in flash.

  • Read our Olympus E-M1 Review

  • Outstanding high ISO performance; excellent dynamic range; 4K video recording (via uncompressed HDMI); XAVC S option for HD video; Slightly improved battery life over A7/A7R; Built-in Wi-Fi & NFC connectivity.

  • 4K video requires expensive external recorder; Sluggish startup time; Loud shutter; Silent Shooting mode hurts image quality; Lacks a built-in, pop-up flash; Limited selection of native Sony FE lenses.

  • Read our Sony A7S Review

The Competition

Compared to Olympus E-M5

Olympus E-M1
Olympus E-M5
  • $1099
  • 4/3
  • Focus peaking
  • Fast startup
  • $900
  • 4/3
  • Thinner
  • Shoots 60p video

Compare Olympus E-M1 vs Olympus E-M5

Sony A7S
Olympus E-M5
  • $1998
  • 35mm
  • Focus peaking
  • Larger sensor
  • $900
  • 4/3
  • Lens selection
  • In-Camera Image Stabilization

Compare Sony A7S vs Olympus E-M5

Compared to Panasonic GH3

Olympus E-M1
Panasonic GH3
  • $1099
  • 4/3
  • Focus peaking
  • In-Camera Image Stabilization
  • $798
  • 4/3
  • Tilt-swivel screen
  • Longer stills battery life

Compare Olympus E-M1 vs Panasonic GH3

Sony A7S
Panasonic GH3
  • $1998
  • 35mm
  • Focus peaking
  • Larger sensor
  • $798
  • 4/3
  • Tilt-swivel screen
  • Lens selection

Compare Sony A7S vs Panasonic GH3

Compared to Panasonic GH4

Olympus E-M1
Panasonic GH4
  • $1099
  • 4/3
  • In-Camera Image Stabilization
  • On-sensor phase detect
  • $899
  • 4/3
  • Less expensive
  • Tilt-swivel screen

Compare Olympus E-M1 vs Panasonic GH4

Sony A7S
Panasonic GH4
  • $1998
  • 35mm
  • Larger sensor
  • Slower slow-motion
  • $899
  • 4/3
  • Lens selection
  • Less expensive

Compare Sony A7S vs Panasonic GH4

Compared to Panasonic GX8

Olympus E-M1
Panasonic GX8
  • $1099
  • 4/3
  • Fast startup
  • On-sensor phase detect
  • $998
  • 4/3
  • Tilt-swivel screen
  • Shoot 4K video

Compare Olympus E-M1 vs Panasonic GX8

Sony A7S
Panasonic GX8
  • $1998
  • 35mm
  • Larger sensor
  • Bigger pixels
  • $998
  • 4/3
  • Lens selection
  • Less expensive

Compare Sony A7S vs Panasonic GX8

Compared to Sony A7S II

Olympus E-M1
Sony A7S II
  • $1099
  • 4/3
  • Lens selection
  • Less expensive
  • $2398
  • 35mm
  • Larger sensor
  • Bigger pixels

Compare Olympus E-M1 vs Sony A7S II

Sony A7S
Sony A7S II
  • $1998
  • 35mm
  • Less expensive
  • Fast startup
  • $2398
  • 35mm
  • In-Camera Image Stabilization
  • Shoot 4K video

Compare Sony A7S vs Sony A7S II

Compare Other Cameras?