• APS-C 366.6mm2
  • 20.1 megapixels
  • ISO 100 - 51,200
  • APS-C 364.3mm2
  • 19.6 megapixels
  • ISO 100 - 6400

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Differences

Pentax K-S1 advantages over Sigma sd Quattro

  • Lens selection
    Excellent vs Limited
    Better lens selection gives you more options
  • In-Camera Image Stabilization
    Yes vs No
    Reduces the effects of camera shake at slower shutter speeds
  • Internal flash
    Internal flash vs None
    Useful in a pinch for fill flash
  • 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
  • Shoots 60p video
    Yes vs No
    A faster framerate can give you more editing options
  • Faster shutter
    1/6000 vs 1/4000 sec
    Shoot wide open in bright light
  • Higher extended ISO
    51200 vs 6400 ISO
    Higher extended ISO can give more low-light flexibility

Sigma sd Quattro advantages over Pentax K-S1

  • On-sensor phase detect
    Yes vs No
    Usually improves live view and video AF performance
  • More dots on screen
    1620k vs 922k dots
    Can mean greater resolution or a brighter screen
  • More viewfinder magnification
    0.73x vs 0.63x
    Get a bigger view of the scene through the eye-level viewfinder

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
  • 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

  • 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
  • Top deck display
    Neither provide
    Check settings with a screen on top of the camera
  • 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

User reviews

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Your purchases support this site

Buy the Pentax K-S1
Body Only
  • Body Only
  • Kit with 18-55mm and 50-200mm Lenses
All K-S1 Deals

Your purchases support this site

Buy the Sigma sd Quattro
Body Only
  • Body Only
  • Kit with 30mm f/1.4 Art Lens
All sd Quattro Deals

Review Excerpt

The Competition

Compared to Sony A58

Pentax K-S1
Sony A58
  • $502
  • APS-C
  • Lens selection
  • Higher effective ISO
  • $598
  • APS-C
  • Less expensive
  • In-camera panoramas

Compare Pentax K-S1 vs Sony A58

Sigma sd Quattro
Sony A58
  • $699
  • APS-C
  • On-sensor phase detect
  • More dots on screen
  • $598
  • APS-C
  • Lens selection
  • In-Camera Image Stabilization

Compare Sigma sd Quattro vs Sony A58

Compared to Sony A3000

Pentax K-S1
Sony A3000
  • $502
  • APS-C
  • Lens selection
  • In-Camera Image Stabilization
  • $500
  • APS-C
  • Less expensive
  • In-camera panoramas

Compare Pentax K-S1 vs Sony A3000

Sigma sd Quattro
Sony A3000
  • $699
  • APS-C
  • On-sensor phase detect
  • HDMI out
  • $500
  • APS-C
  • Lens selection
  • In-camera panoramas

Compare Sigma sd Quattro vs Sony A3000

Compared to Nikon D5500

Pentax K-S1
Nikon D5500
  • $502
  • APS-C
  • Focus peaking
  • In-Camera Image Stabilization
  • $697
  • APS-C
  • Tilt-swivel screen
  • Touchscreen

Compare Pentax K-S1 vs Nikon D5500

Sigma sd Quattro
Nikon D5500
  • $699
  • APS-C
  • Focus peaking
  • On-sensor phase detect
  • $697
  • APS-C
  • Lens selection
  • Less expensive

Compare Sigma sd Quattro vs Nikon D5500

Compared to Pentax K-S2

Pentax K-S1
Pentax K-S2
  • $502
  • APS-C
  • Higher-res screen
  • $499
  • APS-C
  • Tilt-swivel screen
  • Built-in Wi-Fi

Compare Pentax K-S1 vs Pentax K-S2

Sigma sd Quattro
Pentax K-S2
  • $699
  • APS-C
  • On-sensor phase detect
  • More dots on screen
  • $499
  • APS-C
  • Tilt-swivel screen
  • Lens selection

Compare Sigma sd Quattro vs Pentax K-S2

Compared to Fujifilm X-H1

Pentax K-S1
Fujifilm X-H1
  • $502
  • APS-C
  • Lens selection
  • Longer stills battery life
  • $1199
  • APS-C
  • Shoot 4K video
  • Touchscreen

Compare Pentax K-S1 vs Fujifilm X-H1

Sigma sd Quattro
Fujifilm X-H1
  • $699
  • APS-C
  • More dots on screen
  • $1199
  • APS-C
  • Lens selection
  • In-Camera Image Stabilization

Compare Sigma sd Quattro vs Fujifilm X-H1

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