Resolution Chart Comparison

Shots here are of our '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 set to deliver approximately 80% luminance of white area.

Canon EOS-1DS Mark III (4.3 MB, 21 MP) Nikon D3 (3.2 KB; 12 MP)
Canon EOS 5D (3,552 KB; 12.8 MP) Canon EOS-1D Mark III (2.2 MB, 10.1 MP)

Canon EOS-1DS Mark III

Nikon D3

Canon EOS 5D Canon EOS-1D Mark III

Canon EOS-1DS Mark III Nikon D3
Canon EOS 5D Canon EOS-1D Mark III

Canon EOS-1DS Mark III Nikon D3
Canon EOS 5D Canon EOS-1D Mark III

Measurable results

Camera Measurement
Nikon D3 Horizontal LPH 2200  2600 
Vertical LPH 2200  2600 
Canon EOS-1Ds
Mark III
Horizontal LPH 2700  3300 
Vertical LPH 2700  3300 
Canon EOS-1D
Mark III
Horizontal LPH * 2100  2400 
Vertical LPH 2050  2350 
Canon EOS 5D Horizontal LPH 2300  2500 
Vertical LPH 2000  2500 
Canon EOS-1Ds Mark II (not shown) Horiz LPH 2800  3000 
Vert LPH 2400  3100 

* 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 resolution 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 resolution Detail beyond camera's definition (becomes aliased)

The EOS-1Ds Mark III sets a new standard for digital SLR resolution, though it's fair to say that the bar is being raised by smaller and smaller increments these days (the EOS-1Ds Mark III gives you around 10% more resolution than the previous 'best in class', its predecessor the Mark II). If you want the maximum possible detail from a 35mm format interchangeable lens camera then this is the one for you.