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Compared to...

Colour Chart Comparison

Using the test charts in our review database we can compare the Minolta DiMAGE X to three other 2 megapixel compact digital cameras: Canon A20, Canon Digital IXUS 300 (S300 ELPH) and the Nikon Coolpix 775.

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.

Minolta DiMAGE X Canon PowerShot A20
Canon Digital IXUS 300 (S300 ELPH) Nikon Coolpix 775

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.

Patch Minolta
DiMAGE X
 
Canon PowerShot
A20
 
Canon Digital
IXUS 300 (S300)
 
Nikon
Coolpix 775
Black 22,22,22 17,17,17 21,21,21 16,20,19
       
Middle Gray 91,91,91 88,91,91 98,98,98 97,98,98
       
White 210,210,210 205,206,202 213,213,209 202,204,200
       
Magenta 206,30,89 194,33,99 204,38,112 219,31,83
       
Red 199,22,33 188,22,30 201,30,40 212,17,9
       
Yellow 225,198,70 198,185,26 206,193,31 187,189,39
       
Green 1,148,97 19,124,57 25,131,63 0,156,77
       
Cyan 0,162,243 25,145,200 30,155,209 0,186,214
       
Blue 43,39,84 23,27,88 24,30,93 26,41,100
       

As you can see the DiMAGE X manages to white balance well (the white, gray and black patches are perfect). It exhibits strong reds but weak blues, I was surprised to see so much blue 'leaking' into the solid green patch.

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, all settings factory default. Exposure compensation +0.7 EV for all cameras.

Horizontal resolution Vertical resolution 5 degree diagonal res.
Minolta DiMAGE X
Canon PowerShot A20
Canon Digital IXUS 300 (S300 ELPH)
Nikon Coolpix 775

Measurable findings (three measurements taken for each camera):

Camera Measurement Absolute Res. Extinction Res.
Minolta DiMAGE X Horiz LPH 750  900 
Vert LPH 750  * 1000 
5° Diagonal LPH 700  900 
Canon PowerShot A20 Horiz LPH 820  * 1000 
Vert LPH 800  1050 
Diagonal LPH 800  900 
Canon Digital IXUS 300 Horiz LPH 820  *1000 
Vert LPH 800  1050 
Diagonal LPH 800  900 
Nikon Coolpix 775 Horiz LPH 750  * 950 
Vert LPH 750  1000 
Diagonal LPH 800  900 

* Moiré is visible

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.

It's really not good news, the DiMAGE X recorded the lowest resolution measurements of any modern 2 megapixel digital camera. For horizontal resolution it's almost the same as Nikon's Coolpix 775 but vertical resolution is notably less. I'm afraid to say that the innovative lens system just can't deliver enough resolution for the 2 megapixel sensor.

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