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Compared to... (contd.)

Colour Chart Comparison

Now we can compare the Coolpix 995 to a few of other cameras. Using samples from our test archives, we will now compare its image quality to the Nikon Coolpix 990, Canon PowerShot G1 and Olympus C-3040Z.

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.

Nikon Coolpix 995 Nikon Coolpix 990
Canon PowerShot G1 Olympus C-3040Z

A quick visual inspection shows that the 995's colours are indeed better than the 990. Most notably greens and yellows. Otherwise there's very little difference. Again, the G1 shows the most "balanced" (equal saturation for different primaries) with specifically better blues (although the G1 colour chart does have a very slight red cast).

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

Nikon Coolpix
995

Nikon Coolpix
990
Canon PowerShot
G1

Olympus
C-3040Z

Black 23,26,24 22,21,21 34,32,34 30,30,30
       
Middle Gray 98,99,98 104,104,104 97,96,102 102,102,100
       
White 213,210,210 201,201,201 214,208,208 201,202,201
       
Magenta 206,38,118 211,44,114 204,41,121 205,36,103
       
Red 197,29,47 203,34,42 189,31,53 195,29,36
       
Yellow 217,185,26 198,190,73 205,193,59 191,185,61
       
Green 9,136,57 5,149,63 26,149,73 8,136,61
       
Cyan 51,162,199 47,172,188 58,180,230 31,157,183
       
Blue 53,45,104 60,50,112 55,49,117 41,33,84
       

Overall the 995 does well, colours are strong and slightly "purer" than the 990. It is only really let down by a slightly weak blue (something you could easily correct in Photoshop with a selective colour saturation increase). Don't forget also that you can boost colour on the 995 by setting the saturation adjustment value to +1.

Kodak Q60 target - Coolpix 995 vs. Coolpix 990

Below you'll see Kodak's Q60 colour target shot with the Coolpix 995, if you roll your mouse over it it will be replaced by the same chart shot with the Coolpix 990. This makes visualising the difference in colour reproduction between the two cameras far easier. (Ignore the slight distortion, this is due to pincushion at the slightly different focal lengths).

Roll mouse over image above to see Coolpix 990 Q60

Click here to download full Coolpix 995 Q60 (1,041 KB)
Click here to download full Coolpix 990 Q60 (1,236 KB)

Red Channel Noise

Something we noticed early on with the current crop of 3 megapixel cameras was a certain amount of noise in the red channel. This was most visible in the light blue of skies or painted walls. Our colour patch test chart turned out to be a good "leveller" and a way to measure the performance of one camera to the next.

The samples below are of 40 x 40 blocks cropped from the colour comparison charts above of the Blue and Cyan patches. Each block is then broken down into it's red green and blue channels and reflected as such directly below.

Things are definetly improved, noise is still visible in the red channel of both patches (dark and light blue), however it's 'different' and this makes it less noticeable than the 990. Again, this supports what we saw from the surprisingly clean ISO 100 and 200 test images earlier in the review. Looks like 'noisy sky syndrome' won't be as much of a problem for the Coolpix 995.

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. Sharpening set to 'Normal' for 995 & 990.

Nikon Coolpix 995
Nikon Coolpix 990
Canon PowerShot G1
Olympus C-3040Z

Measurable findings (three measurements taken for each camera):

Camera Measurement Absolute Res. Extinction Res.
Nikon
Coolpix 995
Horiz LPH 900* 1300
Vert LPH 900 1400
5o Diagonal LPH 900 n/a
Nikon
Coolpix 990
Horiz LPH 900 1300
Vert LPH 900 1400
5o Diagonal LPH 900 n/a
Canon
PowerShot G1
Horiz LPH 950* 1300
Vert LPH 950* 1400
5o Diagonal LPH 900* n/a
Olympus
C-3040Z
Horiz LPH 1000* 1300
Vert LPH 1000* 1350
5o Diagonal LPH 900* 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)
5o Diagonal Lines set at 5o 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 expected the 995 performs virtually identically to its older brother the 990 (although the 990 does look slightly sharper). If anything moiré is more visible and the corners of the frame are softer with the 995.

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