Resolution Chart Comparison

Comparison cameras:

  • Casio EX-Z850 (8MP, 3x zoom)
  • Canon PowerShot S80 (8MP, 3.6x zoom)
  • FinePix F10 Zoom (6 MP, 3 x zoom)
  • Panasonic DMC-LX1 (8MP, 4x zoom)
  • Olympus Stylus 800 / Mju 800 Digital (8 MP, 3x zoom)
  • Casio EX-Z750 (7MP, 3x zoom)

Shots here are of our standard resolution chart (version one or two). This 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. (Note that on version two of our chart the vertical resolution 1000 - 2000 lines have been horizontally flipped but are otherwise identical). 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 auto, settings all factory default. If possible aperture was selected for optimum sharpness. Exposure compensation +0.3 EV to +1.3 EV.

Casio EX-Z850 (3,969 KB; 8 MP) Canon PowerShot S80 (2,889 KB; 8 MP)
Panasonic DMC-LX1 (3,382 KB; 8.3 MP) Fujifilm FinePix F10 (2,938 KB; 6 MP)
Olympus Stylus 800 (3,356 KB; 8 MP) Casio EX-Z750 (3,991 KB; 7 MP)

Resolution chart crops

Casio EX-Z850 Canon PowerShot S80
Panasonic DMC-LX1 Fujifilm FinePix F10 Zoom
Olympus Stylus 800 Casio EX-Z750
Casio EX-Z850 Canon PowerShot S80
Panasonic DMC-LX1 Fujifilm FinePix F10 Zoom
Olympus Stylus 800 Casio EX-Z750

Measurable findings

Camera Measurement
Casio EX-Z850 Horiz LPH 1600 1900
Vert LPH 1550 1950
5° Diagonal LPH +1000 n/a
Canon PowerShot S80 Horiz LPH 1700 2000
Vert LPH 1700 * 2200
5° Diagonal LPH +1000 n/a
Fujifilm FinePix F10 Horiz LPH 1650 +2000
Vert LPH 1750 +2000
5° Diagonal LPH + 1000 n/a 
Panasonic DMC-LX1 Horiz LPH 1500 *1900
Vert LPH 1600 *1950
5° Diagonal LPH + 1000 n/a 
Olympus Stylus 800 Horiz LPH 1750 + * 2000
Vert LPH * 1700 + * 2000
5° Diagonal LPH + 1000 n/a
Casio EX-Z750 Horizontal LPH 1650 +* 2000
Vertical LPH 1600 *1900
5° Diagonal LPH + 1000 n/a 
* Moiré is visible
# Jagged diagonals
+ 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)

Proof, were it ever needed, that any advantage to be gained by moving from 7 to 8 megapixels is dubious to say the least; no matter how many times we re-tested the EX-Z850 it produced marginally lower resolution than its predecessor, the EX-Z750. Given both cameras have the same lens (which is probably the limiting factor, resolution-wise) we might have expected the results to be the same, but there is no denying that there is a little more very high frequency detail in the 7MP image. We suspect the limiting factor here is noise - the 8MP chip needs a little more noise reduction even at ISO 50, and though you'll rarely see it in real-world shots, this does have a blurring effect on very fine detail. The higher contrast and higher sharpening of the Z750 image also makes the image look more detailed, though as we are talking about frequencies very near to Nyquist I doubt there is any real difference in resolution - you'll just get sharper 'looking' fine detail with the Z750.

Comparisons with its predecessor aside, the EX-Z850 is producing fairly clean results (though there is a little evidence of sharpening), and the images are clean, moiré-free and have resolution that puts them in the top half (though not at the top) of the current crop of 8MP compacts.