Resolution Chart Comparison

Comparison cameras:

  • Canon PowerShot SD500 (7 MP, 3x zoom)
  • Canon PowerShot S70 (7 MP, 3.6x zoom)
  • Sony Cyber-shot DSC-P150 (7 MP, 3x zoom)
  • Nikon Coolpix 7900 (7 MP, 3x zoom)

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 1/100th lines per picture height. Thus a value of 15 equates to 1500 lines per picture height.

Studio light, cameras set to auto, settings all factory default. If possible aperture was selected for optimum sharpness. Exposure compensation +0.7 EV to +1.3 EV.

Canon PowerShot SD500 (2,415 KB; 7 MP) Canon PowerShot S70 (2,378 KB; 7 MP)
Nikon Coolpix 7900 (2,348 KB; 7 MP) Sony DSC-P150 (2,681 KB; 7 MP)

Resolution Chart crops

Canon PowerShot SD500 Canon PowerShot S70
Nikon Coolpix 7900 Sony DSC-P150
Canon PowerShot SD500 Canon PowerShot S70
Nikon Coolpix 7900 Sony DSC-P150

Measurable findings

Camera Measurement
Canon PowerShot SD500 Horiz LPH 1550 1850
Vert LPH * 1700 +* 2000
5° Diagonal LPH + 1000 n/a 
Canon PowerShot S70 Horiz LPH 1550 * 1800
Vert LPH 1650 +* 2000
5° Diagonal LPH + 1000 n/a 
Nikon Coolpix 7900 Horizontal LPH 1500 + 1750
Vertical LPH 1500 1750
5° Diagonal LPH + 1000 n/a 
Sony DSC-P150 Horizontal LPH 1500 1700
Vertical LPH 1500 1750
5° Diagonal LPH + 1000 n/a 

* Moiré is visible
+ Chart maximum
LPH Lines per Picture Height (to allow for different aspect ratios the measurement is the same for horizontal and vertical)
5° Diagonal Lines set at 5° diagonal
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)
n/a Not Available (above the capability of the test chart)
n/v Not Visible (not visible on test results)

Although they're not the cleanest files here (there is fairly strong moiré at higher frequencies), the SD500 is pulling a surprising amount of detail out of our test chart - almost as good a result as the S70, though the S70's image is cleaner and slightly sharper. For such a small camera to be effectively 'off the chart' is a tribute to Canon's lens designers, and - we suspect - also an indication that the 7MP sensor has a much weaker anti-alias filter than it's lower pixel count predecessors. It's only a pity that this excellent resolution doesn't always show itself in photographs of everyday scenes.