The learning curve for the Pentax
Optio T30 is very short thanks to its touch screen interface,
and the impression left by the system is generally positive.
This said, although the camera is relatively quick to respond
to its controls and exhibits only a slight shutter lag, having
to access a number of camera settings using a series of steps
with the touch screen tends to slow down its use.
Generally, the Optio T30 yields images with a slightly stronger
saturation than what a neutral setting would produce, ideal
when images are printed.
The default metering of the T30
is an averaging system that is quite reliable, delivering
images that are well exposed under a variety of lighting conditions,
and making it rare to need either the centre-weighted or spot
alternatives.
The white balance produces natural
colours in most cases, and its presets for artificial light
(incandescent, fluorescent) are well calibrated. For instance,
the use of the tungsten setting yields very accurate colours
when used indoor with standard household lighting.
But, when inspecting images at 100% on a monitor, some less positive characteristics
become noticeable.
Images appear to be too compressed,
even at the highest image quality. And, although the Optio T30
offers three image quality settings available at all image sizes
— a rare feature on many current compact cameras that
should be lauded— the compression setting of the highest
image quality, hovering around 8:1, is too strong.
The effect of the strong compression
is visible at 100%: the finer details in images loose definition
and artefacts such as marbling in areas of uniform colour
can be seen. As a result it becomes difficult to evaluate
the sharpness of the lens with confidence.
Furthermore, images captured at the widest angle of the lens
reveal a bit of barrel distortion when there are straight
lines in the subject that are aligned near the edges of the
frame.
Aperture: f2.7, shutter speed: 1/4 sec., 64 ISO.
The effect disappears as soon as the
zoom is used and the focal length moves from the wide angle
end, and there is no detectable pincushion distortion at the
telephoto end. Moreover, there is no visible chromatic aberration
at any point in the focal length range of the lens, even when
the subject contains very strong contrasts.
Another factor that enters into
any consideration of the image quality of the T30 is noise.
The Optio T30 yields noise-free images at 64 and 100 ISO when used with bright
outdoor light. As of 200 ISO, however, shadow areas contain
some random colour specs — noise — that invade
uniform colour areas of images at the 400 ISO level. Furthermore,
given poor or low light, even 64 ISO level images can contain
noise, albeit only in shadow areas.
From 800 ISO upwards images loose
sharpness and are of very limited use, making us wonder why
Pentax would have implemented an ISO range that goes up to
3200 ISO on the camera...
The built-in flash is effective
when used in conjunction with other light sources and is effective
at opening up shadows. Moreover, the white balance reacts
well to mixed lighting situations, resulting in images that
have colours that are quite close to reality.
The range of the flash is quite short, however, and as soon
as the zoom is used, the smaller aperture available to the
camera requires increasing the CCD sensitivity, something
that must be accomplished with care so as to avoid noise degrading
the image quality.
Noise and compression combine
to limit the size of prints that can be produced from the
Optio T30’s images, as large size prints can reveal
artefacts. Nevertheless, with its 7 megapixel CCD, the Pentax
Optio T30 yields images that can be printed out to a 4 x 6
inch (10 x 15 cm) size without any difficulty. The colour
saturation is well-suited to prints and, at such a standard
size, images are quite detailed.
Image Quality
