• APS-C 369.7mm2
  • 14.2 megapixels
  • ISO 200 - 12,800
  • APS-C 369.0mm2
  • 14.8 megapixels
  • ISO 100 - 6400

Buy From

Differences

Sony DSLR-A550 advantages over Sigma SD1 Merrill

  • Lens selection
    Good vs Limited
    Better lens selection gives you more options
  • Less expensive
    $1050 vs $2299 (MSRP)
    Save money for lenses or accessories
  • In-Camera Image Stabilization
    Yes vs No
    Reduces the effects of camera shake at slower shutter speeds
  • Tiltable Screen
    Tiltable vs Fixed
    Tilt the screen for shooting flexbility
  • Fast startup
    ~0.50 vs 4.5 sec
    Faster startup lets you catch the moment
  • HDMI out
    HDMI out vs None
    Use HDMI output to monitor or review video
  • More dots on screen
    922k vs 460k dots
    Can mean greater resolution or a brighter screen
  • Less shutter lag
    0.18 vs 0.38 sec
    Focus and take a photo quickly (wide angle)
  • Faster JPEG shooting
    6.7 fps vs 4.1 fps
    Faster JPEG shooting (burst mode)
  • Bigger JPEG buffer
    15 vs 7 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

Sigma SD1 Merrill advantages over Sony DSLR-A550

  • Pentaprism viewfinder
    Pentaprism vs Pentamirror
    Much better viewfinder picture fidelity
  • More viewfinder magnification
    0.63x vs 0.53x
    Get a bigger view of the scene through the eye-level viewfinder
  • Doesn't require an AA filter
    Yes vs No
    A unique sensor design provides sharp photos without moiré
  • Faster shutter
    1/8000 vs 1/4000 sec
    Shoot wide open in bright light

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
  • 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
  • Touchscreen
    Neither provide
    Interact with your camera just like your smartphone
  • In-camera panoramas
    Neither provide
    Stitches multiple shots into a panoramic photo
  • Built-in Wi-Fi
    Neither provide
    Share your photos wirelessly
  • 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
  • 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

Buy From

Your purchases support this site

Buy the Sony DSLR-A550

Your purchases support this site

Buy the Sigma SD1 Merrill
Kit with 18-200mm lens
  • Kit with 18-200mm lens
  • Body Only
  • Kit with 17-50mm lens
All SD1 Merrill Deals

Review Excerpt

The Competition

Compared to Canon 50D

Sony DSLR-A550
Canon 50D
  • $859
  • APS-C
  • Less expensive
  • In-Camera Image Stabilization
  • $1000
  • APS-C
  • Lens selection
  • Fast startup

Compare Sony DSLR-A550 vs Canon 50D

Sigma SD1 Merrill
Canon 50D
  • $8492
  • APS-C
  • Doesn't require an AA filter
  • Wider angle kit lens
  • $1000
  • APS-C
  • Lens selection
  • Less expensive

Compare Sigma SD1 Merrill vs Canon 50D

Compared to Nikon D300S

Sony DSLR-A550
Nikon D300S
  • $859
  • APS-C
  • In-Camera Image Stabilization
  • Tiltable Screen
  • $1697
  • APS-C
  • Lens selection
  • Fast startup

Compare Sony DSLR-A550 vs Nikon D300S

Sigma SD1 Merrill
Nikon D300S
  • $8492
  • APS-C
  • More pixels
  • Doesn't require an AA filter
  • $1697
  • APS-C
  • Lens selection
  • Fast startup

Compare Sigma SD1 Merrill vs Nikon D300S

Compared to Sony DSLR-A500

Sony DSLR-A550
Sony DSLR-A500
  • $859
  • APS-C
  • More dots on screen
  • More pixels
  • $850
  • APS-C
  • Less expensive

Compare Sony DSLR-A550 vs Sony DSLR-A500

Sigma SD1 Merrill
Sony DSLR-A500
  • $8492
  • APS-C
  • Pentaprism viewfinder
  • More dots on screen
  • $850
  • APS-C
  • Lens selection
  • Less expensive

Compare Sigma SD1 Merrill vs Sony DSLR-A500

Compared to Pentax K-5

Sony DSLR-A550
Pentax K-5
  • $859
  • APS-C
  • Tiltable Screen
  • Longer stills battery life
  • $800
  • APS-C
  • Lens selection
  • Higher effective ISO

Compare Sony DSLR-A550 vs Pentax K-5

Sigma SD1 Merrill
Pentax K-5
  • $8492
  • APS-C
  • Doesn't require an AA filter
  • $800
  • APS-C
  • Lens selection
  • In-Camera Image Stabilization

Compare Sigma SD1 Merrill vs Pentax K-5

Compared to Nikon D500

Sony DSLR-A550
Nikon D500
  • $859
  • APS-C
  • In-Camera Image Stabilization
  • Bigger pixels
  • $1598
  • APS-C
  • Lens selection
  • Shoot 4K video

Compare Sony DSLR-A550 vs Nikon D500

Sigma SD1 Merrill
Nikon D500
  • $8492
  • APS-C
  • Bigger pixels
  • Internal flash
  • $1598
  • APS-C
  • Lens selection
  • Shoot 4K video

Compare Sigma SD1 Merrill vs Nikon D500

Compare Other Cameras?