Resolution Chart Comparison

Shots here are of our new 'version two' resolution chart which provides for measurement of resolution up to 4000 LPH (Lines Per Picture Height). A value of 20 equates to 2000 lines per picture height. For each camera the relevant prime lens was used. The chart is shot at a full range of apertures and the sharpest image selected. Studio light, cameras set to aperture priority (optimum aperture selected), image parameters default. Exposure compensation +0.7 EV to +1.3 EV.

Sony Alpha DSLR-A100 (2,213 KB; 10 MP) Canon EOS 30D (2,409 KB; 8.2 MP)
Sony DSC-R1 (3,739 KB; 10 MP) Nikon D200 (2,728 KB; 10 MP)

Sony Alpha DSLR-A100 Canon EOS 30D
Sony DSC-R1 Nikon D200

Sony Alpha DSLR-A100 Canon EOS 30D
Sony DSC-R1 Nikon D200

Sony Alpha DSLR-A100 Canon EOS 30D
Sony DSC-R1 Nikon D200

Measurable findings (three measurements taken for each camera):

Camera Measurement
Absolute
resolution
Extinction
resolution
Sony Alpha DSLR-A100 Horizontal LPH 2200  2900 
Vertical LPH 1800  2800 
Canon EOS 30D Horizontal LPH 1850  2100 
Vertical LPH 1650  2100 
Sony DSC-R1 Horiz LPH 1950  2400 
Vert LPH 1700  2300 
Nikon D200 Horizontal LPH 2100  2250 
Vertical LPH 1700  2200 

* Moire is visible
+ Chart maximum
LPH Lines per Picture Height (to allow for different aspect ratios the measurement is the same for horizontal and vertical)
Absolute res. Point at which all lines of a resolution bar are still visible and defined, beyond this resolution loss of detail occurs (below Nyquist frequency).
Extinction res. Detail beyond camera's definition (becomes aliased)

We were a little surprised to see the Alpha DSLR-A100 beating the Nikon D200 on our resolution charts, but that's how things played out. The A100 delivered slightly more absolute horizontal and vertical resolution than the D200 and continued detail much further (the 'extinction resolution'). Here also we're seeing more of an advantage from ten megapixels over the eight megapixels of the Canon EOS 30D, however these numbers mean fractional improvements and as we have already seen don't always equate to a visibly more detailed 'real life' image.