Main
Model
Price
Advantages
launch
Announced
Body type
Camera subcategory
Sensor
Effective pixels
Max resolution
Sensor size
Sensor type
Image ratio w:h
Other resolutions
Sensor photo detectors
Image
ISO
Boosted ISO (maximum)
White balance presets
Custom white balance
Image stabilization
Uncompressed format
JPEG quality levels
Photography features
Minimum shutter speed
Maximum shutter speed
Aperture priority
Shutter priority
Manual exposure mode
Subject / scene modes
Built-in flash
Flash range
External flash
Flash modes
Continuous drive
Self-timer
Metering modes
Exposure compensation
AE Bracketing
WB Bracketing
Screen / viewfinder
Articulated LCD
Screen size
Screen dots
Touch screen
Live view
Viewfinder type
Screen type
Videography features
Resolutions
File Format
Microphone
Speaker
Optics & Focus
Focal length (equiv.)
Optical zoom
Autofocus
Digital zoom
Manual focus
Normal focus range
Maximum aperture
Physical
Weight (inc. batteries)
Dimensions
Environmentally sealed
Battery
Battery details
Battery Life (CIPA)
Storage
Storage types
Storage included
Connectivity
USB
HDMI
Remote control
Wireless
Other features
Orientation sensor
Timelapse recording
GPS
Samples
Videos
Summary
The GR maximum resolution of 4928 x 3264 pixels (16 megapixels) is better in comparison with the Sigma DP2 highest resolution of 2640 x 1760 pixels (5 megapixels). The GR has larger sensor compared to the Sigma DP2: APS-C (23.7 x 15.7 mm) versus APS-C (20.7 x 13.8 mm). This is the most important difference between these cameras as big sensor allows you to produce photos of the better quality. The GR offers a wider ISO range of 100-25600 than 50-800 ISO range of the Sigma DP2. Such ISO numbers allow you to produce good quality photos in low light conditions. The GR provides more presets of white balance - 9. This specification gives you more control over colour.
The GR screen is better as it has more screen dots 1,230,000 in compare to 230,000 dots of the Sigma DP2 display. The higher dot count screen is better for reviewing pictures on your camera. The GR has better minimum (300 seconds) and fastest (1/4000 second) shutter speeds.
The GR weighs 245g that is 35g less in comparison with the weight of the Sigma DP2.
Taking into account the above-mentioned differences the Ricoh GR is the best choice. Check the lowest price on Amazon.