• APS-C 366.6mm2
  • 24.4 megapixels
  • ISO 100 - 51,200
  • 4/3 226.2mm2
  • 20.4 megapixels
  • ISO 200 - 6400

Buy From

Differences

Pentax K-3 advantages over Olympus E-M5 III

  • Larger sensor
    APS-C vs 4/3
    More sensor area. Bigger is (generally) better.
  • Bigger pixels
    ~ 3.91 vs 3.36 microns
    Better low-light and dynamic range (all else equal)
  • Longer stills battery life
    More info 560 vs 310 shots
    Capture more photos
  • Internal flash
    Internal flash vs None
    Useful in a pinch for fill flash
  • Top deck display
    Yes vs No
    Check settings with a screen on top of the camera
  • More pixels
    24.4 vs 20.4 megapixels
    Higher resolution photos
  • Dual card slots
    Yes vs No
    Gives you more storage flexibility
  • Headphone jack
    Yes vs No
    Monitor audio recording while you shoot video
  • Optional anti-aliasing filter
    Optional vs None
    Lets you choose sharper photos or reduced moiré
  • Bigger JPEG buffer
    75 vs 26 shots
    Take more JPEG shots before waiting (burst mode)
  • Higher extended ISO
    51200 vs 25600 ISO
    Higher extended ISO can give more low-light flexibility

Olympus E-M5 III advantages over Pentax K-3

  • Tilt-swivel screen
    Tilt-swivel vs none
    Tilt and swivel the screen for maximum shooting flexibility
  • Shoot 4K video
    4K (DCI) vs 1080p
    Make sure you have a fast computer
  • Touchscreen
    Touch vs No touch
    Interact with your camera just like your smartphone
  • High resolution composite
    Yes vs No
    Combine multiple shots to form a super hi-res version
  • Built-in Wi-Fi
    Wi-Fi vs None
    Share your photos wirelessly
  • Built-in Bluetooth
    Yes vs No
    Always-on wireless connectivity
  • On-sensor phase detect
    Yes vs No
    Usually improves live view and video AF performance
  • Thinner
    49 mm vs 77 mm
    Thinner
  • Newer
    5 years vs 11 years old
    Newer cameras often support more advanced features
  • Longer exposure
    60 vs 30 sec
    Long exposures for night shots
  • Faster JPEG shooting
    30.0 fps vs 7.1 fps
    Faster JPEG shooting (burst mode)
  • Faster RAW shooting
    30.0 fps vs 7.1 fps
    Faster RAW shooting in burst mode
  • Slow-motion videos
    Yes vs No
    Shoot slow-motion videos
  • Faster shutter
    1/32000 vs 1/8000 sec
    Shoot wide open in bright light

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
  • In-Camera Image Stabilization
    Both provide
    Reduces the effects of camera shake at slower shutter speeds
  • 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

  • In-camera panoramas
    Neither provide
    Stitches multiple shots into a panoramic photo
  • NFC
    Neither provide
    Simplifies pairing your camera with supported phones
  • Built-in GPS
    Neither provide
    Geotag your photos

User reviews

Buy From

Your purchases support this site

Buy the Pentax K-3

Your purchases support this site

Buy the Olympus E-M5 III

Review Excerpt

  • Top-notch image quality; Great ergonomics in a compact body; Unique on-demand low-pass filtering; Broad sensitivity range; Large and bright viewfinder for an APS-C camera; Dual card slots; Optional Wi-Fi remote control

  • AE Lock button is poorly located; Below-average battery life for a DSLR; Rather dated-looking menu system; Requires a different battery grip accessory than its predecessors; Less third-party support than some rivals

  • Improved image quality; Very good dynamic range & high ISO performance for a modern MFT sensor; Very fast AF; Excellent image stabilization; 4K video recording; Weather-sealed build quality.

  • Below average battery life; Small size can be awkward with long, heavy lenses; One SD card slot.

The Competition

Compared to Nikon D7100

Pentax K-3
Nikon D7100
  • $699
  • APS-C
  • Focus peaking
  • In-Camera Image Stabilization
  • $690
  • APS-C
  • Fast startup
  • Longer stills battery life
Olympus E-M5 III
Nikon D7100
  • $924
  • 4/3
  • Tilt-swivel screen
  • Focus peaking
  • $690
  • APS-C
  • Less expensive
  • Larger sensor

Compared to Nikon D5300

Pentax K-3
Nikon D5300
  • $699
  • APS-C
  • Focus peaking
  • In-Camera Image Stabilization
  • $549
  • APS-C
  • Tilt-swivel screen
  • Fast startup
Olympus E-M5 III
Nikon D5300
  • $924
  • 4/3
  • Focus peaking
  • In-Camera Image Stabilization
  • $549
  • APS-C
  • Less expensive
  • Larger sensor

Compared to Nikon D7200

Pentax K-3
Nikon D7200
  • $699
  • APS-C
  • Focus peaking
  • In-Camera Image Stabilization
  • $1016
  • APS-C
  • Fast startup
  • Built-in Wi-Fi
Olympus E-M5 III
Nikon D7200
  • $924
  • 4/3
  • Focus peaking
  • Less expensive
  • $1016
  • APS-C
  • Larger sensor
  • Bigger pixels

Compared to Panasonic G100

Pentax K-3
Panasonic G100
  • $699
  • APS-C
  • Larger sensor
  • In-Camera Image Stabilization
  • $599
  • 4/3
  • Tilt-swivel screen
  • Shoot 4K video
Olympus E-M5 III
Panasonic G100
  • $924
  • 4/3
  • In-Camera Image Stabilization
  • High resolution composite
  • $599
  • 4/3
  • Less expensive
  • In-camera panoramas

Compared to Olympus E-M10 IV

Pentax K-3
Olympus E-M10 IV
  • $699
  • APS-C
  • Larger sensor
  • Bigger pixels
  • $649
  • 4/3
  • Shoot 4K video
  • Touchscreen
Olympus E-M5 III
Olympus E-M10 IV
  • $924
  • 4/3
  • Tilt-swivel screen
  • High resolution composite
  • $649
  • 4/3
  • Less expensive
  • Longer video battery life
Compare Other Cameras?