• APS-C 366.6mm2
  • 24.3 megapixels
  • ISO 100 - 25,600
  • APS-C 361.2mm2
  • 25.7 megapixels
  • ISO 100 - 1,600,000

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Differences

Sony A5100 advantages over Pentax K-3 III

  • Less expensive
    $448 vs $2344
    Save money for lenses or accessories
  • In-camera panoramas
    Yes vs No
    Stitches multiple shots into a panoramic photo
  • Tiltable Screen
    Tiltable vs Fixed
    Tilt the screen for shooting flexbility
  • NFC
    Yes vs No
    Simplifies pairing your camera with supported phones
  • On-sensor phase detect
    Yes vs No
    Usually improves live view and video AF performance
  • Internal flash
    Internal flash vs None
    Useful in a pinch for fill flash
  • Thinner
    35 mm vs 73 mm
    Thinner
  • Bigger JPEG buffer
    67 vs 30 shots
    Take more JPEG shots before waiting (burst mode)

Pentax K-3 III advantages over Sony A5100

  • Lens selection
    Excellent vs Good
    Better lens selection gives you more options
  • Eye-level viewfinder
    Eye-level vs Rear display only
    You'll be able to frame photos even when the sun is out
  • In-Camera Image Stabilization
    Yes vs No
    Reduces the effects of camera shake at slower shutter speeds
  • Shoot 4K video
    4K (UHD) vs 1080p
    Make sure you have a fast computer
  • High resolution composite
    Yes vs No
    Combine multiple shots to form a super hi-res version
  • Built-in Bluetooth
    Yes vs No
    Always-on wireless connectivity
  • Longer stills battery life
    More info 800 vs 400 shots
    Capture more photos
  • Top deck display
    Yes vs No
    Check settings with a screen on top of the camera
  • External Mic Jack
    Jack vs No jack
    Improved sound fidelity when shooting video
  • Newer
    3 years vs 10 years old
    Newer cameras often support more advanced features
  • Higher-res screen
    540k vs 230k pixels
    More detail on the screen lets you judge focus and composition
  • Hot shoe
    Hot shoe vs None
    Off-camera flashes open new possibilities
  • 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 Fixed
    Lets you choose sharper photos or reduced moiré
  • Faster JPEG shooting
    12.0 fps vs 6.0 fps
    Faster JPEG shooting (burst mode)
  • Faster shutter
    1/8000 vs 1/4000 sec
    Shoot wide open in bright light
  • Higher extended ISO
    1600000 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
  • Touchscreen
    Both provide
    Interact with your camera just like your smartphone
  • Built-in Wi-Fi
    Both provide
    Share your photos wirelessly
  • HDMI out
    Both provide
    Use HDMI output to monitor or review video
  • 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 GPS
    Neither provide
    Geotag your photos
  • Slow-motion videos
    Neither provide
    Shoot slow-motion videos

User reviews

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  • Body Only
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Review Excerpt

  • Very small and comfortable form factor; Very good image quality for its class; New dual video record function; Quick autofocus and good dynamic range.

  • Lacks an EVF and external mode dial; No hot shoe; JPEG processing at higher ISOs not as good as some competing mid-level models.

  • Read our Sony A5100 Review

The Competition

Compared to Samsung NX1100

Sony A5100
Samsung NX1100
  • $348
  • APS-C
  • Lens selection
  • Focus peaking
  • $450
  • APS-C
  • Higher-res screen
  • Hot shoe

Compare Sony A5100 vs Samsung NX1100

Pentax K-3 III
Samsung NX1100
  • $1847
  • APS-C
  • Lens selection
  • Focus peaking
  • $450
  • APS-C
  • Thinner

Compare Pentax K-3 III vs Samsung NX1100

Compared to Sony NEX-5T

Sony A5100
Sony NEX-5T
  • $348
  • APS-C
  • Higher effective ISO
  • Longer stills battery life
  • $299
  • APS-C
  • Bigger pixels
  • Higher-res screen

Compare Sony A5100 vs Sony NEX-5T

Pentax K-3 III
Sony NEX-5T
  • $1847
  • APS-C
  • Lens selection
  • Eye-level viewfinder
  • $299
  • APS-C
  • Bigger pixels
  • In-camera panoramas

Compare Pentax K-3 III vs Sony NEX-5T

Compared to Sony A5000

Sony A5100
Sony A5000
  • $348
  • APS-C
  • Touchscreen
  • Higher effective ISO
  • $298
  • APS-C
  • Less expensive

Compare Sony A5100 vs Sony A5000

Pentax K-3 III
Sony A5000
  • $1847
  • APS-C
  • Lens selection
  • Eye-level viewfinder
  • $298
  • APS-C
  • Less expensive
  • In-camera panoramas

Compare Pentax K-3 III vs Sony A5000

Compared to Pentax KP

Sony A5100
Pentax KP
  • $348
  • APS-C
  • Less expensive
  • Touchscreen
  • $999
  • APS-C
  • Lens selection
  • Eye-level viewfinder

Compare Sony A5100 vs Pentax KP

Pentax K-3 III
Pentax KP
  • $1847
  • APS-C
  • Shoot 4K video
  • Touchscreen
  • $999
  • APS-C
  • Less expensive
  • Tiltable Screen

Compare Pentax K-3 III vs Pentax KP

Compared to Canon 90D

Sony A5100
Canon 90D
  • $348
  • APS-C
  • Less expensive
  • Focus peaking
  • $1199
  • APS-C
  • Lens selection
  • Tilt-swivel screen

Compare Sony A5100 vs Canon 90D

Pentax K-3 III
Canon 90D
  • $1847
  • APS-C
  • Focus peaking
  • In-Camera Image Stabilization
  • $1199
  • APS-C
  • Less expensive
  • Tilt-swivel screen

Compare Pentax K-3 III vs Canon 90D

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