
ISO (Sensitivity) and visible noise
ISO equivalence on a digital camera is the ability to increase
the sensitivity of the CCD to allow for faster shutter speeds and/or better
performance in low light. The way this works in a digital camera is by
"turning up the volume" on the CCD's signal amplifiers, nothing
is without its price however and doing so also amplifies any noise that
may be present and often affects colour saturation.
The 885 features three selectable ISO sensitivities of
100, 200, and 400 as well as the same Auto mode we've seen before which
appears to vary sensitivity between ISO 100 and 200 depending on available
light.
| Good light (10 EV) |
Low light (3 EV) |
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| ISO 100, 1/73 sec, F2.8 |
ISO 100, 1.0 sec, F2.8 |
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| ISO 200, 1/141 sec,
F2.8 |
ISO 200, 1/2 sec, F2.8 |
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| ISO 400, 1/270 sec,
F2.8 |
ISO 400, 1/3 sec, F2.8 |
Clean images at ISO 100 and 200, although if you dive
in real close and take a look at some of the white areas of the image
you'll see horizontally layered chroma (colour) noise, it's not that visible
but is still there. This chroma noise becomes more visible at ISO 400.
But, on the whole, this is an impressive performance for a 3 megapixel
digital camera.

White Balance
Just like the 995 the 885 exhibited a magenta cast with
Auto white balance under incandescent lights. Clearly auto white balance
works best under natural light. Kudos to Nikon for including the fine
tuneable white balance option on the 885, it allows you to subtly adjust
the pre-programmed white balances to suit your common shooting environments.
The manual preset option produces consistently accurate
balance and colour hue. Note how much stronger reds appear to be compared
to the rest of the colour spectrum (I'll comment more on this later in
the review).
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| Outdoors, Auto |
Outdoors, Sunny |
Outdoors, Manual |
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| Incandescent, Auto |
Incandescent, Incandescent |
Incandescent, Manual |
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| Fluorescent, Auto |
Fluorescent, Fluorescent |
Fluorescent, Manual |
First word indicates the light in which the shot was taken, the second
indicates the selected white balance mode.

Macro Focus
Although the 885 doesn't have the 9xx series macro power it is certainly
very capable in its own right, more so than most 3 megapixel compacts.
The cameras optimum macro focal length range is at the wide end of zoom
and is indicated on the LCD monitor by the macro icon turning yellow.
At full wide angle macros with the lens very close to the subject are
possible, zooming a little further (10 mm as a native focal length) and
we are still within the optimum focal length range but must move back
from the subject. Here we get approximately 4.8 cm horizontal frame coverage
with less barrel distortion than at full wide angle.
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| Lens @ 8 mm, approx. horizontal coverage
4.0 cm (1.6 in) - some barrel distortion |
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| Lens @ 10 mm, approx. horizontal coverage
4.8 cm (1.9 in) |
The bank note close-ups are good examples of some lens softness (corners
and extreme edges) at its maximum aperture (F2.8 at wide angle).

Low Light Focus
In
a new addition to our reviews we'll now be measuring the minimum amount
of light under which the camera can still focus. The focus target is our
lens distortion test chart (shown here on the right), camera is positioned
exactly 2 m (6.6 ft) away.
Light levels are gradually dropped until the camera can no longer focus.
This is carried out at both wide angle and telephoto zoom positions (as
more light reaches the focusing systems with a larger aperture).
This test target is the optimum type of subject for most "contrast
detect" AF systems (as it has a vertical line at its center), you
should consider the results below the best you could expect to achieve.
| Lens position |
Aperture |
Lowest light focus |
| Wide angle (38 mm) |
F2.8 |
1.1 EV (5.4 Lux / 0.5 foot-candle) |
| Telephoto (114 mm) |
F4.9 |
4.0 EV (40 Lux / 3.7 foot-candle) |
Light intensity
(Lux) = 2.5 x 2^EV (@ ISO 100), 10.76391 Lux = 1 foot-candle (fc)
As we can see the zoom position has a large influence on low light focus
ability simply because the lens' maximum aperture is much smaller at telephoto
and thus less light gets through to the CCD and so focusing is more difficult.
Overall the 885 performed approximately the same as its bigger brother
the 995. I'd really like to see Nikon implementing an AF assist lamp on
their digital cameras in the future.
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