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Noise

This is one of the first cameras we've seen that uses the new 10.3 megapixel, 1/2.3" sensor that crops up in a large number of the cameras announced around PMA in January 2008. And, if this is anything to go by, we're not looking forward to the rest of them. The individual photosites on such a sensor will be even smaller than on the 12MP 1/1.8" sensors that appeared in the second half of 2007 and none of them were particularly stellar performers.

Small photosites (which receive very little light), densely packed (increasing the risk of electronic interference), are always likely to generate noise. Adding high ISO settings that further restrict the amount of light reaching each photosite by using shorter shutter speeds, just makes matters worse. Let's see if our expectations will be confounded...

ISO 80
ISO 100
ISO 200
ISO 400
100% Crops
ISO 800

ISO 1600

ISO 3200

No. Although the lowest two sensitivity settings are handling noise quite well, it's also clear that they're doing so with extensive noise reduction. Even at the lowest setting, there's little in the way of detail in the hairline on the stamp. Instead, artefacts are clearly visible on the border between the Queen's face and the plain background, this is likely to be a combination of jpeg compression, noise reduction and sharpening - it won't be visible on any sensibly-sized print but is worrying at what should be the camera's highest quality setting.

Chroma noise is apparent in the grays at all sensitivity levels but becomes really obvious at ISO 400 and 800 before being smothered by noise reduction. Luminance noise isn't too obvious in the blacks or grays until ISO 800 but that's probably because noise reduction is being so heavily applied. This noise reduction is smearing away detail at ISO 400 and by ISO 1600 there's almost no recognizable image left. This doesn't bode well for this season's cameras.

Noise graph

Indicated ISO sensitivity is on the horizontal axis of this graph, standard deviation of luminosity is on the vertical axis.

Chroma and Luminance Gray noise dropping between ISO 80 and 100? That's a pretty sure sign that noise reduction is being applied right at the lowest ISO settings. Even with the extensive noise reduction we're seeing applied to the images at ISO 400 and above, the measured noise levels are still very high. The suppression of Chroma noise, particularly visible in the gray areas of the crops at ISO 1600 can clearly been seen on the graph.

Low contrast detail

What the crops and graph don't show is the effect of noise reduction on low contrast fine detail such as hair, fur or foliage. An inevitable side effect of noise removal is that this kind of detail is also blurred or smeared, resulting in a loss of 'texture'. In this test the crops below show the effect of the noise reduction on such texture (fur) as you move up the ISO range.

100% Crops
ISO 80 ISO 100 ISO 200
ISO 400 ISO 800 ISO 1600

At its lowest setting, the image from the T300 is able to distinguish between subtle shades of color, though the detail looks a little 'guessed-at' in places. There is a slight grittiness to the image that suggests over-sharpening is helping achieve these results. Moving to ISO 100 there is a very slight loss of contrast but again the ability to differentiate between tones is good. The problems begin at ISO 200, where the different tones are losing the distinction between them and the fine detail there was is being replaced by smearing and artifacts.

However, the real fun starts at ISO 400 at which point contrast drops dramatically and posterization leaves only three distinct shades of yellow. Almost all the fine detail has vanished and aberrant artifacts are the only things implying any sense of texture at all. Photos with grass in them would be end up looking like Fuzzy Felt at ISO 400 and above. The story gets increasingly bad from there on, with essentially two shades of yellow and no detail at all at ISO 1600. Click here for the ISO 3200 sample if you can't already imagine what a blotchy yellow square would look like.

Optical image stabilization

Because the T300 doesn't give any direct control over the shutter speeds or apertures it uses, we have not been able to conduct our usual tests to check how effective the Super Steady Shot image stabilization is. However, we did shoot a series of shots in lighting conditions that demanded unrealistically long shutter speeds for hand-holding. The images below show the difference between having image stabilization on and off in the same shooting conditions.

Both images were taken at 1/5 sec at a focal length of 29mm (equiv.) so represent an exposure just under 3 stops stops slower than the traditional 1/focal length guide for achieving steady images. The image taken with Super Steady Shot on is not perfect but it's much closer to being usable than the shots taken with stabilization turned off.

Image stabilization OFF
100% crop
Image stabilization ON 100% crop
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