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Article first published on AllAboutSymbian
It's tempting to think of the cameras in the Nokia N90,
the N73 and the N93, as just flashier versions of the hardware in the
likes of the N70, 5500, N71 and E70 (to name but four models with
two megapixel cameras). But the presence of a proper focussing lens,
together with more control of exposure, makes a huge difference and
different rules apply.
In one sense, taking good photos is much harder, as you
can rarely now 'point and shoot'. On the other hand, the final results
can potentially be far superior, especially if photographing something
fairly close. Helping you up this learning curve is what this tutorial
is all about (and thanks to this post on the Symbian Freak board for
inspiration).
- Firstly and most importantly of all, just as with my
article on video recording, light is everything. It's
photons of light that trigger charge in the camera's sensor, and the
more of them the more accurate the reading from each sensor pixel. In
good light, there's more than enough information being gathered and
your Nseries camera will produce results comparable to those from
standalone cameras. In poor light, either in the evening or under flash
conditions or in a dimly lit room, there simply aren't enough photons
hitting each pixel for the sensor to be absolutely sure what value to
report, which is why you get 'noise', flecks of random colours in your
photo. In a standalone camera, the sensor pixels are bigger and each
gathers in more photons, so you don't notice the same degree of noise.
It's also worth noting that you may also have problems in very bright
light with any digital camera, as photons 'overflow' from one pixel to
the next, with the result that you sometimes see 'smearing' around
bright sections of the image.
Be aware of the light conditions at all times and try to anticipate the
effect the level will have on your Nseries camera. It also goes without
saying that the obvious rules of photography apply, such as not
shooting towards the light source unless you're trying for a
special effect.
On the N93, understand that using the optical zoom will decrease the
amount of light getting to the main sensor, so only zoom in if you're
confident there's enough light to cope.
A zoomed in night image showing the typical random
coloured flecks of digital 'noise'.
 Next, understand
how the autofocus system in these Nseries devices works. The
image within the central graticule is sampled many times a
second when you slightly depress the shutter button, with the lens
moving backwards or forwards in an attempt to maximise the
contrast of edge detail within the graticule. Now, this system normally
works well enough, but it can fall down if there's not enough light
(see point 1. above) or if the object in this part of the image doesn't
have any detail that's suitable for contrast sampling.
In this case, it's best to move the centre of your composition
slightly, to something that's the same distance away but which has
better detail. Once focussing has been achieved on this, you can keep
the shutter partially depressed and move the image centre back to the
original subject, before finally pressing the shutter all the way down.
For typical 'point and shoot' landscape shots, where there's no real
close-up foreground, the auto-focus system will probably make a
mess of things, so make sure you change the shooting mode to
'Landscape', in which the auto-focus is disabled and the camera behaves
just as that in an 'infinite focus' lesser device, such as that on
other camera smartphones.
A typical scene, zoomed in, showing the horrible
out-of-focus effect if you forget to use 'landscape' mode when there's
no foreground subject to focus on.
- Take a little time (if possible) to think
about adjusting the settings from 'automatic' values. For
example, using 'Night' as the 'Shooting mode' forces the camera to use
a longer exposure time, thus letting more photons in and reducing
noise, at the expense of blurry images of anything that's moving - or
the whole scene if your hand isn't steady enough when pressing the
shutter button. 'White balance' is also worth fiddling with if you've
got the time to set a shot up properly - colours seem different under
different lighting conditions and this is your chance to allow for this
factor. Finally, 'Exposure value' is invaluable if you like playing
around with light, perhaps shooting into a bright light (decreasing the
exposure value) or trying to pick a dark subject out of a bright
background (increasing the exposure value). By default, your Nseries
camera software will try and average out the light intensity across
your image, which is often not what you actually want. In each case,
adjusting the exposure by a couple of stops can make a big difference
and give you more control.
 
An example of knocking down exposure when focussing
on a bright subject.... and what happens if you don't put up the
exposure when trying to focus on a dark subject in a bright
environment...
- Learn to press the shutter properly.
First of all, there's shutter lag, which is quite well known. Having
pressed the shutter button, there's a lag of up to second while the
exposure level is calculated and implemented, so learn to allow for
this in terms of composition and in terms of staying 'in position' for
a second or so after pressing the button. In addition, the shutter will
be 'open' (whether it's a mechanical shutter (as in the N93) or an
electronic one (as in the N90) for a specific duration (e.g. 50
milliseconds) and if you're moving the smartphone during this time then
your photo will have a degree of blur. So it pays to brace yourself
(hold the smartphone in two hands, stand with your legs apart and hold
your breath momentarily) and gently 'squeeze' the shutter rather than
stabbing at it.
 
The difference between not bothering and taking
care to hold the Nseries smartphone steady for a second or two after
squeezing the shutter button...
Over and over again, I see people complaining about
picture quality or, sometimes, simply presenting poor photos. None of
these Nseries auto-focus cameras are perfect and, to be honest, none
are as good as a top standalone camera, because of the degree of
miniaturisation needed, but used with care you can achieve some very
respectable results.
Hopefully learning the four steps above improve your
still photography.
Steve Litchfield, 19 December 2006
Bonus link: Improving your N93
video recording
Article first published on AllAboutSymbian
All text (C) Steve Litchfield, 2006
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