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.
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 |
Absolute
resolution |
Extinction
resolution |
| 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. |
