Compared to... (contd.)
Now we'll compare the DiMAGE S404 to a few other cameras from our test archives. Here we're comparing colour and resolution to the Minolta DiMAGE S304, Canon PowerShot G2 and Sony DSC-S85.
Colour Chart Comparison
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.
As per other samples in this review the S404 image has been converted to the sRGB colour space using the Minolta Image Viewer application [info]
|Minolta DiMAGE S404 (Resaved as sRGB)||Minolta DiMAGE S304 (Resaved as sRGB)|
|Canon PowerShot G2||Sony DSC-S85|
Notice the clearly blue cast white balance, after taking my first test shot I went back and retried this a few times but always go the same result. The S404 does seem to have a tendancy to produce a bluer white balance than the other cameras (this has the effect of making whites look whiter).
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.
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 S404|
|Canon PowerShot G2|
Measurable findings (three measurements taken for each camera):
|Camera||Measurement||Absolute Res.||Extinction Res.|
|Minolta DiMAGE S404||Horiz LPH||* 1150||* 1350|
|Vert LPH||* 1100||* 1350|
|5° Diagonal LPH||800||n/a|
|Canon PowerShot G2||Horiz LPH||1250||* 1450|
|Vert LPH||1200||* 1500|
|5° Diagonal LPH||1000||n/a|
|Sony DSC-S85||Horiz LPH||1250||* 1650|
|5° Diagonal LPH||1000||n/a|
* 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.
The DiMAGE S404 performs fairly well, clearly it's not quite up there with the best, although vertical resolution is closer than horizontal. What is much more noticeable on the S404 is the strong yellow / blue colour moiré as line frequency enters the camera's limit. Interestingly the S404 suffers worst on the 5° diagonal pattern where it produces moiré.