Get Sigma dp Quattro at B&H Photo. I am a fan of the Sigma DP Merrill line. As this was written, get 22% off on the Sigma DP Merrill line.
See also the review of the Sigma dp2 Quattro.
The Sigma dp0 Quattro extends the focal length range of the Sigma dp Quattro line. Its 14mm f/4 lens is equivalent to a 21mm f/5.6 on a full frame camera.
These two demanding scenes are perfect ETTR exposures that max-out the dynamic range of the Sigma dp0 Quattro.
Sigma dp0 Quattro Aperture Series: Backlit Bristlecones
Sigma dp0 Quattro Aperture Series: Bristlecone Log, Frontlit
Sharpness is assesed in shadow areas in particular. Discussion of depth of field and appropriate aperture are included, along with a discussion of diffraction-mitigating sharpening.
Also shown are the Sigma Photo Pro processing settings, RawDigger histogram, and Photoshop adjustments following conversion to 16-bit TIF. Includes color and black and white for both images. Entire-frame images at sizes up to full resolution from f/4 - 7.1 - 9.
f4 @ 1/200 sec, ISO 100; 2015-07-27 15:08:53[low-res image for bot]
SIGMA dp0 Quattro + 14mm f/4 @ 21.4mm (14mm)
f4 @ 1/500 sec, ISO 100; 2015-07-27 15:22:43[low-res image for bot]
SIGMA dp0 Quattro + unspecifiedLens @ 21.4mm (14mm)