Resolution Chart Comparison

Shots here are of the PIMA/ISO 12233 standard resolution test chart (more of which are available in our comparison database). This resolution chart allows us to measure the actual performance of the lens and sensor system. It measures the ability of the camera to resolve lines at gradually higher resolutions and enables us to provide a definitive value for comparison purposes. Values on the chart are 1/100^th lines per picture height. So a value of 15 equates to 1500 lines per picture height.

Studio light, cameras set to auto, all settings factory default. Aperture selected for optimum sharpness. Exposure compensation +0.7 EV to +1.3 EV. Sigma SD9 image processed with default parameters.

Sigma SD9	Canon EOS-D60
Nikon D100	Fujifilm S2 Pro (6.1 mp size)

Sigma SD9	Canon EOS-D60
Nikon D100	Fujifilm S2 Pro (6.1 mp size)

Sigma SD9	Canon EOS-D60
Nikon D100	Fujifilm S2 Pro (6.1 mp size)

Sigma SD9	Canon EOS-D60
Nikon D100	Fujifilm S2 Pro (6.1 mp size)

Sigma SD9	Canon EOS-D60
Nikon D100	Fujifilm S2 Pro (6.1 mp size)

Measurable findings (three measurements taken for each camera):

Definition of terms:

The SD9 is capable of delivering all nine individual lines of the horizontal or vertical resolution bars up to its maximum absolute resolution (sensor vertical pixel count) and slightly beyond. Note also that because the X3 sensor doesn't need a color filter array it doesn't suffer from color moiré.. Absolute resolution is just less than the Canon EOS-D60, Nikon D100 and Fujifilm S2 Pro (at 6 mp).

However, because the X3 sensor doesn't use a low pass (anti-alias) filter it is able to resolve detail all the way up to Nyquist. Beyond Nyquist the system will alias without any objectionable color moiré. Where a Bayer sensor camera would turn detail beyond Nyquist (such as distant grass texture) into a single plane of blurred color the SD9 will continue to reproduce some individual pixel detail (without color moiré).