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 1/100th lines per picture height. So a value of 15 equates to 1500 lines per picture height. For each camera the relevant 50 mm prime lens was used. The chart is shot at a full range of apertures and the sharpest image selected.
Studio light, cameras set to auto, all settings factory default. Aperture selected for optimum sharpness. Exposure compensation +0.7 EV to +1.3 EV.
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| Konica Minolta 7D |
Canon EOS 20D |
 |
 |
| Nikon D70 |
Pentax *ist D |
 |
 |
| Konica Minolta 7D |
Canon EOS 20D |
 |
 |
| Nikon D70 |
Pentax *ist D |
 |
 |
| Konica Minolta 7D |
Canon EOS 20D |
 |
 |
| Nikon D70 |
Pentax *ist D |
 |
 |
| Konica Minolta 7D |
Canon EOS 20D |
 |
 |
| Nikon D70 |
Pentax *ist D |
Measurable findings (three measurements taken for each camera):
| Camera |
Measurement |
Absolute
resolution |
Extinction
resolution |
| Konica Minolta 7D |
Horiz LPH |
1600 |
1750 |
| Vert LPH |
1400 |
1700 |
| Canon EOS 20D |
Horiz LPH |
1850 |
+ 2000 |
| Vert LPH |
1650 |
+ 2000 |
| Nikon D70 |
Horiz LPH |
1600 |
* 1850 |
| Vert LPH |
1450 |
* 1850 |
| Pentax *ist D |
Horiz LPH |
1500 |
* 1800 |
| Vert LPH |
1300 |
* 1700 |
| * |
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) |
| 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) |
The 7D delivered about as much resolution as the Nikon D70 (also the same as the Canon EOS 300D), its strong anti-alias filter means there's less moire past the point of absolute resolution but that in actual fact its ability to resolve detail is about the same. Obviously the 7D loses out to the eight megapixel EOS 20D here, the difference most obvious in the horizontal resolution crop.
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