Pentax K-3 vs Sony A7S

Sony A7S advantages over Pentax K-3

• Larger sensor
  35mm vs APS-C
  More sensor area. Bigger is (generally) better.
• Bigger pixels
  ~ 8.40 vs 3.91 microns
  Better low-light and dynamic range (all else equal)
• In-camera panoramas
  Yes vs No
  Stitches multiple shots into a panoramic photo
• Tiltable Screen
  Tiltable vs Fixed
  Tilt the screen for shooting flexbility
• Built-in Wi-Fi
  Wi-Fi vs None
  Share your photos wirelessly
• NFC
  Yes vs No
  Simplifies pairing your camera with supported phones
• Higher effective ISO

  Higher effective ISO

  Maximum effective ISO is an estimate of the highest sensitivity at which a camera can capture excellent quality photos.

  Cameras with higher effective ISO will be better choices for indoor photography, night shooting, and indoor sports photography, especially if you intend to make large prints.

  You can learn more at our glossary entry.

  Maximum effective ISO test data courtesy of DxO Mark.

  A7S test data on DxO Mark K-3 test data on DxO Mark
  3,702 vs 1,216 iso
  Take photos in low light with less noise
• Thinner
  48 mm vs 77 mm
  Thinner
• More viewfinder magnification
  0.71x vs 0.63x
  Get a bigger view of the scene through the eye-level viewfinder
• Bigger RAW buffer
  39 vs 24 shots
  Larger buffer for RAW shots (burst mode)
• Slow-motion videos
  Yes vs No
  Shoot slow-motion videos
• Higher extended ISO
  409600 vs 51200 ISO
  Higher extended ISO can give more low-light flexibility