• APS-C 369.7mm2
  • 16.2 megapixels
  • ISO 100 - 12,800
  • 4/3 224.9mm2
  • 16.1 megapixels
  • ISO 200 - 25,600

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Differences

Sony A55 advantages over Olympus E-M10

  • Larger sensor
    APS-C vs 4/3
    More sensor area. Bigger is (generally) better.
  • Bigger pixels
    ~ 4.82 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
  • Fast startup
    ~0.90 vs 1.3 sec
    Faster startup lets you catch the moment
  • Built-in GPS
    GPS vs None
    Geotag your photos
  • External Mic Jack
    Jack vs No jack
    Improved sound fidelity when shooting video
  • More viewfinder magnification
    0.73x vs 0.58x
    Get a bigger view of the scene through the eye-level viewfinder
  • Has anti-aliasing filter
    Filter vs No Filter
    Reduces unsightly moiré in photos
  • Faster JPEG shooting
    9.0 fps vs 8.1 fps
    Faster JPEG shooting (burst mode)
  • Bigger JPEG buffer
    32 vs 19 shots
    Take more JPEG shots before waiting (burst mode)

Olympus E-M10 advantages over Sony A55

  • Lens selection
    Excellent vs Good
    Better lens selection gives you more options
  • Focus peaking
    Peaker vs Non-peaker
    Your camera will highlight what's in focus
  • Touchscreen
    Touch vs No touch
    Interact with your camera just like your smartphone
  • Built-in Wi-Fi
    Wi-Fi vs None
    Share your photos wirelessly
  • Thinner
    45 mm vs 84 mm
    Thinner
  • Higher max flash sync
    1/250 vs 1/160 sec
    Reduce the effect of ambient light in flash shots
  • Lighter weight
    515g vs 727g
    Lighter weight
  • Shoots 1080p video
    Yes vs No
    You'll want this if you shoot video
  • Lacks anti-aliasing filter
    No Filter vs Filter
    Enjoy sharper photos
  • Longer exposure
    60 vs 30 sec
    Long exposures for night shots

Similarities

Common Strengths

  • Eye-level viewfinder
    Both provide
    You'll be able to frame photos even when the sun is out
  • In-Camera Image Stabilization
    Both provide
    Reduces the effects of camera shake at slower shutter speeds
  • Tiltable Screen
    Both provide
    Tilt the screen for shooting flexbility
  • Internal flash
    Both provide
    Useful in a pinch for fill flash
  • 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

  • Built-in Bluetooth
    Neither provide
    Always-on wireless connectivity
  • On-sensor phase detect
    Neither provide
    Usually improves live view and video AF performance
  • 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
  • Headphone jack
    Neither provide
    Monitor audio recording while you shoot video
  • Slow-motion videos
    Neither provide
    Shoot slow-motion videos

User reviews

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Buy the Olympus E-M10
Body Only
  • Body Only
  • Kit with 14-42mm Lens
All E-M10 Deals

Review Excerpt

  • Great image quality especially from RAW files; Excellent dynamic range for a Four Thirds sensor; Very good high ISO performance; Realistic colors and excellent hue accuracy; Built-in Wi-Fi with remote control and sharing features; Improved HD video; Lightweight and very portable; Built-in pop-up flash; Minimal EVF lag time.

  • Contrast-Detect AF struggles with small and low-contrast subjects; Mediocre battery life; No external microphone or headphone jack; Mediocre burst speed with continuous AF; No weather sealing; Heavy-handed high ISO noise reduction.

  • Read our Olympus E-M10 Review

The Competition

Compared to Canon T2i

Sony A55
Canon T2i
  • $734
  • APS-C
  • Larger sensor
  • In-Camera Image Stabilization
  • $692
  • APS-C
  • Lens selection
  • Fast startup

Compare Sony A55 vs Canon T2i

Olympus E-M10
Canon T2i
  • $399
  • 4/3
  • Focus peaking
  • In-Camera Image Stabilization
  • $692
  • APS-C
  • Larger sensor
  • Fast startup

Compare Olympus E-M10 vs Canon T2i

Compared to Sony A33

Sony A55
Sony A33
  • $734
  • APS-C
  • Higher effective ISO
  • Built-in GPS
  • $540
  • APS-C

Compare Sony A55 vs Sony A33

Olympus E-M10
Sony A33
  • $399
  • 4/3
  • Lens selection
  • Focus peaking
  • $540
  • APS-C
  • Larger sensor
  • Bigger pixels

Compare Olympus E-M10 vs Sony A33

Compared to Sony A35

Sony A55
Sony A35
  • $734
  • APS-C
  • Tiltable Screen
  • Built-in GPS
  • $567
  • APS-C
  • Less expensive
  • Longer stills battery life

Compare Sony A55 vs Sony A35

Olympus E-M10
Sony A35
  • $399
  • 4/3
  • Lens selection
  • Focus peaking
  • $567
  • APS-C
  • Larger sensor
  • Bigger pixels

Compare Olympus E-M10 vs Sony A35

Compared to Panasonic GX7

Sony A55
Panasonic GX7
  • $734
  • APS-C
  • Less expensive
  • Larger sensor
  • $648
  • 4/3
  • Lens selection
  • Focus peaking

Compare Sony A55 vs Panasonic GX7

Olympus E-M10
Panasonic GX7
  • $399
  • 4/3
  • Less expensive
  • Higher effective ISO
  • $648
  • 4/3
  • In-camera panoramas
  • Fast startup

Compare Olympus E-M10 vs Panasonic GX7

Compared to Olympus E-M10 II

Sony A55
Olympus E-M10 II
  • $734
  • APS-C
  • Larger sensor
  • Bigger pixels
  • $349
  • 4/3
  • Lens selection
  • Focus peaking

Compare Sony A55 vs Olympus E-M10 II

Olympus E-M10
Olympus E-M10 II
  • $399
  • 4/3
  • $349
  • 4/3
  • Fast startup
  • Shoots 24p video

Compare Olympus E-M10 vs Olympus E-M10 II

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