• 0.98 inch 285.7mm2
  • 4.6 megapixels
  • 28.00mm (35mm eq.)
  • APS-C 369.7mm2
  • 16.2 megapixels
  • ISO 100 - 12,800

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Differences

Sigma DP1 advantages over Sony A55

  • Bigger pixels
    ~ 7.84 vs 4.82 microns
    Better low-light and dynamic range (all else equal)
  • Thinner
    50 mm vs 84 mm
    Thinner

Sony A55 advantages over Sigma DP1

  • Larger sensor
    APS-C vs 0.98 inch
    More sensor area. Bigger is (generally) better.
  • Less expensive
    $850 vs $999 (MSRP)
    Save money for lenses or accessories
  • 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
  • In-camera panoramas
    Yes vs No
    Stitches multiple shots into a panoramic photo
  • Tiltable Screen
    Tiltable vs Fixed
    Tilt the screen for shooting flexbility
  • Fast startup
    ~0.90 vs 3.9 sec
    Faster startup lets you catch the moment
  • Built-in GPS
    GPS vs None
    Geotag your photos
  • Longer stills battery life
    More info 330 vs 250 shots
    Capture more photos
  • External Mic Jack
    Jack vs No jack
    Improved sound fidelity when shooting video
  • HDMI out
    HDMI out vs None
    Use HDMI output to monitor or review video
  • More dots on screen
    922k vs 230k dots
    Can mean greater resolution or a brighter screen
  • Less shutter lag
    0.22 vs 1.53 sec
    Focus and take a photo quickly (wide angle)
  • More pixels
    16.2 vs 4.6 megapixels
    Higher resolution photos
  • Longer exposure
    30 vs 15 sec
    Long exposures for night shots
  • Bulb shutter
    Bulb vs No bulb
    Hold the shutter open manually for long exposures
  • Faster JPEG shooting
    9.0 fps vs 3.8 fps
    Faster JPEG shooting (burst mode)
  • Bigger JPEG buffer
    32 vs 3 shots
    Take more JPEG shots before waiting (burst mode)
  • Faster shutter
    1/4000 vs 1/2000 sec
    Shoot wide open in bright light
  • Higher extended ISO
    25600 vs 800 ISO
    Higher extended ISO can give more low-light flexibility

Similarities

Common Strengths

  • Rear display
    Both provide
    Review photos on the back of the camera
  • RAW file ability
    Both provide
    Gives you more flexibility to develop your photos later
  • Internal flash
    Both provide
    Useful in a pinch for fill flash
  • Manual focus
    Both provide
    AF is for the weak. Real photographers focus manually.
  • Hot shoe
    Both provide
    Off-camera flashes open new possibilities

Common Weaknesses

  • Focus peaking
    Neither provide
    Your camera will highlight what's in focus
  • Touchscreen
    Neither provide
    Interact with your camera just like your smartphone
  • Built-in Wi-Fi
    Neither provide
    Share your photos wirelessly
  • Built-in Bluetooth
    Neither provide
    Always-on wireless connectivity
  • On-sensor phase detect
    Neither provide
    Usually improves live view and video AF performance
  • Integrated ND filter
    Neither provide
    Shoot in daylight with a large aperture or slow shutter
  • 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

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Review Excerpt

The Competition

Compared to Pentax K-7

Sigma DP1
Pentax K-7
  • $999
  • 0.98 inch
  • Less expensive
  • Bigger pixels
  • $1300
  • APS-C
  • Larger sensor
  • Eye-level viewfinder

Compare Sigma DP1 vs Pentax K-7

Sony A55
Pentax K-7
  • $734
  • APS-C
  • Less expensive
  • In-camera panoramas
  • $1300
  • APS-C
  • Lens selection
  • Fast startup

Compare Sony A55 vs Pentax K-7

Compared to Canon T2i

Sigma DP1
Canon T2i
  • $999
  • 0.98 inch
  • Bigger pixels
  • Thinner
  • $692
  • APS-C
  • Larger sensor
  • Eye-level viewfinder

Compare Sigma DP1 vs Canon T2i

Sony A55
Canon T2i
  • $734
  • APS-C
  • Larger sensor
  • In-Camera Image Stabilization
  • $692
  • APS-C
  • Lens selection
  • Fast startup

Compare Sony A55 vs Canon T2i

Compared to Sony A33

Sigma DP1
Sony A33
  • $999
  • 0.98 inch
  • Bigger pixels
  • Thinner
  • $540
  • APS-C
  • Less expensive
  • Larger sensor

Compare Sigma DP1 vs Sony A33

Sony A55
Sony A33
  • $734
  • APS-C
  • Higher effective ISO
  • Built-in GPS
  • $540
  • APS-C

Compare Sony A55 vs Sony A33

Compared to Nikon D5100

Sigma DP1
Nikon D5100
  • $999
  • 0.98 inch
  • Bigger pixels
  • Thinner
  • $650
  • APS-C
  • Larger sensor
  • Tilt-swivel screen

Compare Sigma DP1 vs Nikon D5100

Sony A55
Nikon D5100
  • $734
  • APS-C
  • In-Camera Image Stabilization
  • In-camera panoramas
  • $650
  • APS-C
  • Lens selection
  • Tilt-swivel screen

Compare Sony A55 vs Nikon D5100

Compared to Sony A35

Sigma DP1
Sony A35
  • $999
  • 0.98 inch
  • Bigger pixels
  • Thinner
  • $567
  • APS-C
  • Less expensive
  • Larger sensor

Compare Sigma DP1 vs Sony A35

Sony A55
Sony A35
  • $734
  • APS-C
  • Tiltable Screen
  • Built-in GPS
  • $567
  • APS-C
  • Less expensive
  • Longer stills battery life

Compare Sony A55 vs Sony A35

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