• APS-C 369.7mm2
  • 14.6 megapixels
  • ISO 100 - 3200
  • APS-C 355.7mm2
  • 14.2 megapixels
  • ISO 100 - 3200

Buy From

Differences

Pentax K-7 advantages over Nikon D3100

  • In-Camera Image Stabilization
    Yes vs No
    Reduces the effects of camera shake at slower shutter speeds
  • Longer stills battery life
    More info 740 vs 550 shots
    Capture more photos
  • Top deck display
    Yes vs No
    Check settings with a screen on top of the camera
  • More cross-type AF points
    9 vs 1
    Cross-type AF points improve autofocus performance
  • Pentaprism viewfinder
    Pentaprism vs Pentamirror
    Much better viewfinder picture fidelity
  • More dots on screen
    921k vs 230k dots
    Can mean greater resolution or a brighter screen
  • Less shutter lag
    0.09 vs 0.28 sec
    Focus and take a photo quickly (wide angle)
  • More viewfinder magnification
    0.61x vs 0.53x
    Get a bigger view of the scene through the eye-level viewfinder
  • Faster JPEG shooting
    5.2 fps vs 2.9 fps
    Faster JPEG shooting (burst mode)
  • Faster shutter
    1/8000 vs 1/4000 sec
    Shoot wide open in bright light

Nikon D3100 advantages over Pentax K-7

  • Less expensive
    $700 vs $1300 (MSRP)
    Save money for lenses or accessories
  • Fast startup
    ~0.40 vs 0.6 sec
    Faster startup lets you catch the moment
  • Higher effective ISO
    919 vs 536 iso
    Take photos in low light with less noise
  • Shoots 24p video
    Yes vs No
    Gives your movies a big-screen feel
  • Shoots 1080p video
    Yes vs No
    You'll want this if you shoot video
  • Bigger JPEG buffer
    100 vs 20 shots
    Take more JPEG shots before waiting (burst mode)
  • Higher extended ISO
    12800 vs 6400 ISO
    Higher extended ISO can give more low-light flexibility

Similarities

Common Strengths

  • Eye-level viewfinder
    Both provide
    You'll be able to frame photos even when the sun is out
  • 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

  • Focus peaking
    Neither provide
    Your camera will highlight what's in focus
  • Tilt-swivel screen
    Neither provide
    Tilt and swivel the screen for maximum shooting flexibility
  • Touchscreen
    Neither provide
    Interact with your camera just like your smartphone
  • In-camera panoramas
    Neither provide
    Stitches multiple shots into a panoramic photo
  • Tiltable Screen
    Neither provide
    Tilt the screen for shooting flexbility
  • Built-in Wi-Fi
    Neither provide
    Share your photos wirelessly
  • 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
  • On-sensor phase detect
    Neither provide
    Usually improves live view and video AF performance
  • External Mic Jack
    Neither provide
    Improved sound fidelity when shooting video
  • 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

Buy From

Your purchases support this site

Your purchases support this site

Review Excerpt

The Competition

Compared to Samsung GX-20

Pentax K-7
Samsung GX-20
  • $1300
  • APS-C
  • HDMI out
  • More dots on screen
  • $1400
  • APS-C
  • Higher effective ISO
Nikon D3100
Samsung GX-20
  • $700
  • APS-C
  • Less expensive
  • Higher effective ISO
  • $1400
  • APS-C
  • In-Camera Image Stabilization
  • Top deck display

Compared to Sony DSLR-A380

Pentax K-7
Sony DSLR-A380
  • $1300
  • APS-C
  • Lens selection
  • Longer stills battery life
  • $849
  • APS-C
  • Less expensive
  • Tiltable Screen
Nikon D3100
Sony DSLR-A380
  • $700
  • APS-C
  • Lens selection
  • Less expensive
  • $849
  • APS-C
  • In-Camera Image Stabilization
  • Tiltable Screen

Compared to Sony A55

Pentax K-7
Sony A55
  • $1300
  • APS-C
  • Lens selection
  • Fast startup
  • $734
  • APS-C
  • Less expensive
  • In-camera panoramas
Nikon D3100
Sony A55
  • $700
  • APS-C
  • Lens selection
  • Less expensive
  • $734
  • APS-C
  • In-Camera Image Stabilization
  • In-camera panoramas

Compared to Sony A33

Pentax K-7
Sony A33
  • $1300
  • APS-C
  • Lens selection
  • Fast startup
  • $540
  • APS-C
  • Less expensive
  • In-camera panoramas
Nikon D3100
Sony A33
  • $700
  • APS-C
  • Lens selection
  • Fast startup
  • $540
  • APS-C
  • In-Camera Image Stabilization
  • In-camera panoramas

Compared to Nikon D5100

Pentax K-7
Nikon D5100
  • $1300
  • APS-C
  • In-Camera Image Stabilization
  • Top deck display
  • $499
  • APS-C
  • Tilt-swivel screen
  • Higher effective ISO
Nikon D3100
Nikon D5100
  • $700
  • APS-C
  • $499
  • APS-C
  • Tilt-swivel screen
  • Higher effective ISO
Compare Other Cameras?