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Compared to... (contd.)

Colour Chart Comparison

Now we can compare the Finecam S3 to a couple of other cameras, using samples from our test archives we will now compare its image quality (colour and resolution) to the Nikon Coolpix 880, Sony DSC-P1 and Canon PowerShot A20. I've thrown in the A20 as probably the best entry level two megapixel digital camera to see how it fairs against the more expensive Finecam S3.

Colour charts are shot in daylight, Auto White Balance, EV compensation +0.3 (all cameras), measured light ~10 EV. This test is also dependent on the accuracy of the camera's auto white balance, the colour charts are shot in daylight but some camera's white balance is better than others. All cameras are given 20 seconds to "settle" before the shot is taken.

Kyocera Finecam S3 Nikon Coolpix 880
Sony DSC-P1 Canon PowerShot A20

In the table below we're only measuring colour. The RGB values were measured from a VGA reduced image (to average colours, remove noise and eliminate JPEG artifacts) using the Eyedropper tool in Photoshop with a 5 by 5 Average Sample Size.

  Kyocera
Finecam S3
Nikon
Coolpix 880
Sony
DSC-P1
Canon Powershot A20
White 237,235,219 204,204,205 180,187,189 206,206,202
       
Middle Gray 140,142,134 117,117,118 95,102,106 88,91,91
       
Red 232,74,47 210,35,45 175,22,33 187,22,29
       
Green 45,187,79 0,158,83 30,140,64 18,125,56
       
Blue 78,63,150 66,40,107 45,30,126 24,27,86
       

Unhappy with the first sample of our colour patches I went back and re-shot it four or five times, each time the chart had a slight cream cast, this has pushed reds towards orange. Other than this the S3 did a fair job at maintaining all patch colours, notably yellows, greens and blues were strong, these are colours which often suffer in digital camera images.

Resolution 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 8 equates to 800 lines per picture height.

Studio light, cameras set to auto, Exposure compensation +0.7 EV for all cameras.

Kyocera Finecam S3
Nikon Coolpix 880
Sony DSC-P1
Canon PowerShot A20

Measurable findings (three measurements taken for each camera):

Camera Measurement Absolute Res. Extinction Res.
Kyocera Finecam S3 Horiz LPH 820  1100 
Vert LPH 820  1050 
5o Diagonal LPH 800  1000
Nikon Coolpix 880 Horiz LPH  900  1300 
Vert LPH 900  1400 
5o Diagonal LPH 900  n/a 
Sony DSC-P1 Horiz LPH 1000  1350 
Vert LPH 1000  1450 
5o Diagonal LPH 1000  n/a 
Canon PowerShot A20 Horiz LPH 820  1000 
Vert LPH 800  1050 
Diagonal LPH 800  900 

Definition of terms:

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 Resolution Still defined detail (below Nyquist frequency*)
Extinction Resolution Detail beyond camera's definition (becomes a solid gray alias)
n/a Not Available (above the capability of the test chart)
n/v Not Visible (not visible on test results)

* Nyquist frequency defined as the highest spatial frequency where the CCD can still faithfully record
image detail. Beyond the Nyquist frequency aliasing occurs.

As I mentioned earlier in this review the Finecam S3 didn't produce the resolution we'd expect of a three megapixel digital camera. I deliberately included the Canon PowerShot A20 in this comparison because its resolution characteristics are almost identical to that of those of the Finecam S3, and it's a two megapixel digital camera. With a three megapixel sensor the S3 certainly has the potential to resolve good resolution (take a look at the Sony DSC-P1 resolution chart as an example), but it is almost certainly being let down by its lens and internal processing.

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