Compared to...

Studio scene comparison (JPEG)

This is our standard studio scene comparison shot framed to match (as closely as possible) vertical framing. Lighting: daylight simulation, >98% CRI. Crops are 100%. Ambient temperature was approximately 22°C (~72°F).

Sigma DP1 vs. Ricoh GR Digital II

Camera settings:

• Sigma DP1: Aperture Priority, ISO 100, JPEG Large/Fine, Manual WB
  Default Parameters, Self-Timer
   
  
• Ricoh GR Digital II: Aperture Priority, ISO 80
  JPEG Large/Fine, Manual WB, Default Parameters, Self-Timer
  

Sigma DP1	Ricoh GR Digital II
2,398 KB JPEG (2640 x 1760)	3,497 KB JPEG (3648 x 2736)

The Ricoh GR Digital II is, like the Sigma DP1, rather unusual in so far as it is a compact camera that, in a world of superzooms, sports a 28mm (equivalent) prime lens. The rest of the feature set is not completely dissimilar either, both models are clearly targeted at serious photographers who know their way around a camera. The big difference between the two cameras is of course the sensor. While the DP1 records its images on the Foveon X3 sensor which is slightly smaller than the APS-C sized sensors of many DSLRs, the GR Digital II uses a tiny 1/1.8" sensor like it can be found in a lot of compact cameras.

While both lenses are remarkably sharp across the entire frame the Sigma captures a much higher degree of detail. The Ricoh does not perform badly at base ISO and under reasonable light but its output cannot match the Sigma's Foveon images, not even when downscaled.