• APS-C 366.6mm2
  • 24.4 megapixels
  • ISO 100 - 51,200
  • 4/3 226.2mm2
  • 20.4 megapixels
  • ISO 200 - 25,600

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Differences

Pentax K-3 advantages over OM System OM-1

  • Less expensive
    $1150 vs $2200 (MSRP)
    Save money for lenses or accessories
  • 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)
  • 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
  • Optional anti-aliasing filter
    Optional vs None
    Lets you choose sharper photos or reduced moiré

OM System OM-1 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
  • On-sensor phase detect
    Yes vs No
    Usually improves live view and video AF performance
  • Newer
    3 years vs 11 years old
    Newer cameras often support more advanced features
  • Higher-res screen
    540k vs 346k pixels
    More detail on the screen lets you judge focus and composition
  • Longer exposure
    60 vs 30 sec
    Long exposures for night shots
  • Faster JPEG shooting
    120.0 fps vs 7.1 fps
    Faster JPEG shooting (burst mode)
  • Faster shutter
    1/32000 vs 1/8000 sec
    Shoot wide open in bright light
  • Higher extended ISO
    102400 vs 51200 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
  • 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
  • Dual card slots
    Both provide
    Gives you more storage flexibility
  • Headphone jack
    Both provide
    Monitor audio recording while you shoot video
  • 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 Bluetooth
    Neither provide
    Always-on wireless connectivity
  • Built-in GPS
    Neither provide
    Geotag your photos
  • Slow-motion videos
    Neither provide
    Shoot slow-motion videos

User reviews

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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

  • Read our Pentax K-3 Review

The Competition

Compared to Nikon D7100

Pentax K-3
Nikon D7100
  • $699
  • APS-C
  • Focus peaking
  • In-Camera Image Stabilization
  • $745
  • APS-C
  • Fast startup
  • Longer stills battery life

Compare Pentax K-3 vs Nikon D7100

OM System OM-1
Nikon D7100
  • $2200
  • 4/3
  • Focus peaking
  • Tilt-swivel screen
  • $745
  • APS-C
  • Larger sensor
  • Bigger pixels

Compare OM System OM-1 vs Nikon D7100

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

Compare Pentax K-3 vs Nikon D5300

OM System OM-1
Nikon D5300
  • $2200
  • 4/3
  • Focus peaking
  • In-Camera Image Stabilization
  • $549
  • APS-C
  • Larger sensor
  • Bigger pixels

Compare OM System OM-1 vs Nikon D5300

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

Compare Pentax K-3 vs Nikon D7200

OM System OM-1
Nikon D7200
  • $2200
  • 4/3
  • Tilt-swivel screen
  • Focus peaking
  • $1016
  • APS-C
  • Larger sensor
  • Bigger pixels

Compare OM System OM-1 vs Nikon D7200

Compared to Panasonic G95

Pentax K-3
Panasonic G95
  • $699
  • APS-C
  • Larger sensor
  • Bigger pixels
  • $848
  • 4/3
  • Tilt-swivel screen
  • Shoot 4K video

Compare Pentax K-3 vs Panasonic G95

OM System OM-1
Panasonic G95
  • $2200
  • 4/3
  • High resolution composite
  • On-sensor phase detect
  • $848
  • 4/3
  • In-camera panoramas
  • Built-in Bluetooth

Compare OM System OM-1 vs Panasonic G95

Compared to Olympus E-M1 Mark III

Pentax K-3
Olympus E-M1 Mark III
  • $699
  • APS-C
  • Larger sensor
  • Bigger pixels
  • $1649
  • 4/3
  • Tilt-swivel screen
  • Shoot 4K video

Compare Pentax K-3 vs Olympus E-M1 Mark III

OM System OM-1
Olympus E-M1 Mark III
  • $2200
  • 4/3
  • Newer
  • Higher-res screen
  • $1649
  • 4/3

Compare OM System OM-1 vs Olympus E-M1 Mark III

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