Konica Minolta SLR - Manual

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Comparison of 10 digital SLR cameras
for orthodontic photography
D. Bister, Faranak Morderai and R. M. Aveling
Department of Orthodontics, Guy’s Hospital, London, UK
Digital photography is now widely used to document orthodontic patients. High quality intra-oral photography depends on a
satisfactory ‘depth of field’ focus and good illumination. Automatic ‘through the lens’ (TTL) metering is ideal to achieve both
the above aims. Ten current digital single lens reflex (SLR) cameras were tested for use in intra- and extra-oral photography as
used in orthodontics. The manufacturers’ recommended macro-lens and macro-flash were used with each camera. Handling
characteristics, color-reproducibility, quality of the viewfinder and flash recharge time were investigated. No camera took
acceptable images in factory default setting or ‘automatic’ mode: this mode was not present for some cameras (Nikon,
Fujifilm); led to overexposure (Olympus) or poor depth of field (Canon, Konica-Minolta, Pentax), particularly for intra-oral
views. Once adjusted, only Olympus cameras were able to take intra- and extra-oral photographs without the need to change
settings, and were therefore the easiest to use. All other cameras needed adjustments of aperture (Canon, Konica-Minolta,
Pentax), or aperture and flash (Fujifilm, Nikon), making the latter the most complex to use. However, all cameras produced
high quality intra- and extra-oral images, once appropriately adjusted. The resolution of the images is more than satisfactory
for all cameras. There were significant differences relating to the quality of color reproduction, size and brightness of the
viewfinders. The Nikon D100 and Fujifilm S 3 Pro consistently scored best for color fidelity. Pentax and Konica-Minolta had
the largest and brightest viewfinders.
Key words:
;
Refereed paper
Introduction
Intra- and extra-oral photography are widely used to
document orthodontic patients at the start of treatment
and to monitor treatment progress. The ideal character-
istics for intra- and extra-oral photography for dentistry
and orthodontics in particular, are reproducible magni-
fication of the images, good depth of field and
consistent, homogenous illumination. Ideally, all the
above characteristics should be standardized within one
series of images, as well as consistent over long periods
of time.
1,2
‘Depth of field’ is defined as the zone of acceptable
sharpness, and extends in front of and behind the point
of focus. For good depth of field in intra-oral photo-
graphy a small aperture (such as f522) should be used.
Consistent exposure at such settings can best be
achieved by automatic ‘through the lens’ (TTL) meter-
ing.
1
These settings should either be factory pre-set or
should be easily programmable.
Although there are a large number of digital cameras
advertised for use in dental imaging, only Single Lens
Reflex (SLR) cameras consistently fulfill all the above
parameters. Additionally, SLR cameras allow for ‘best
preview’ of the proposed image as the viewfinder shows
the object, as it will appear in the eventual image.
In the pre-digital era the ‘Yashica Dental Eye’ was
produced for intra- and extra-oral photography. This
SLR camera had a 100 mm macro-lens, which was
permanently fixed to the body with a built-in ring-flash. A
macro-lens allows for distortion-free imaging at close
range with high depth of field. The aperture settings were
automatically adjusted when changing the focus from
intra- to extra-oral photography, and was thereby very
user friendly; no changes in camera settings are necessary
between intra- and extra-oral photography. It was also
reasonably priced. The ‘Dental Eye’, however, will not be
made available in the digital format. In this article, this
camera was used as reference, as it had all the above-
mentioned ideal properties for dental photography.
1
Digital SLR cameras have only recently become more
affordable. SLR cameras are now subdivided into two
groups: professional and ‘prosumer’. The professional
group is more expensive, but usually has a range of
advantageous features over the ‘prosumer’ group such
as:
Journal
of
Or
thod
ontics
JOR
3338.3d
11/7/0
6
19
:16:38
The
Charlesworth
Group
,
Wakefield
+44(0)1924
369598
-
Rev
7.51n/W
(Jan
20
2003)
Journal of Orthodontics, Vol. 33, 2006, 000–000
Address for correspondence: D. Bister, Department of
Orthodontics, 22nd Floor, Guy’s and St Thomas’ Foundation
Trust, Guy’s Hospital, London Bridge, London SE1 9RT, UK.
Email: [email protected]
# 2006 British Orthodontic Society DOI 10.1179/146531205225021687