Aim, Materials | Konica Minolta SLR specification

2 D. Bister et al.	Features Section	JO September 2006

19:16:57	Rev 7.51n/W (Jan 20 2003)
11/7/06	369598 -
Journal of Orthodontics JOR3338.3d	The Charlesworth Group, Wakefield +44(0)1924

N higher pixel count (the higher the pixel count the larger the image);

N increased dynamic range (reproducing lighter and darker areas better);

N advanced color reproducibility (ability to reproduce more colors);

N tougher camera-bodies (which are better able to withstand exposure to humidity and dust and are less likely to break on impact);

N longer battery life;

N faster response time to turning the camera on and/ or shutter release delay (delay between turning the camera on/pressing shutter release and actual exposure);

N cleaning the sensor on start-up (to remove dust particles from the sensor).

However some of these features are also found in the ‘prosumer’ group; the Canon EOS 20 D is fast:

0.2second response delay on turning the camera on

and the Olympus E1 has sensor clean.

Although other authors2,3 have previously tested digital cameras, no comprehensive review has recently been undertaken. The professional group was not tested as most of the above-mentioned features are not necessary for dental photography.

For good illumination a macro-ﬂash is ideal: it avoids shadows from cheek retractors at close range and allows for homogeneous illumination of the teeth. Ideally, these macro-ﬂash units should be strong enough for extra-oral photography; thus, avoiding the need for a second ﬂash system. With regards to the macro-lens and macro-ﬂash the manufacturers’ respective devices were tested.

Aim

The aim was to assess 10 digital SLR cameras in the low to medium price range (less than 2500 J for the body), the so called ‘prosumer’ models (comparable to the ‘Yashica Dental Eye’) with manufacturers’ recom- mended macro-lens and ﬂash in terms of:

N ease of use (how many settings needed changing between intra- and extra-oral photography, and how easy these were to accomplish);

N quality of photographs (color reproducibility and pixel count);

N quality of the viewfinder: size and brightness (brighter and larger viewfinders allow easier focusing and handling);

N homogeneity of light on the object and strength of macro-flash (ability to take intra- and extra-oral views with the same flash unit);

COLOUR

FIGURE

Figure 1 Fully assembled unit with macro-lens and macro-ﬂash

N time needed to recharge the macro-flash (time taken between two photographs);

N weight of the unit (including batteries, flash-unit and lens);

N pricing (inclusive of macro-lens and flash, excluding Value Added Tax).

Materials

The cameras tested (shown in Table 1) were single lens reﬂex (SLR), with a macro-ﬂash and a macro-lens, as recommended by the manufacturer. The guide-number for the ﬂash-units represent their power: the higher the number the more powerful the ﬂash unit. One such assembled unit is shown in Figure 1. The Fujiﬁlm S 3 Pro was tested with a Nikon SB 29S Speed-light and 60 mm Nikkor macro-lens.

Standardization of focal length of the macro-lenses was not possible. The choice of macro-lens was determined by availability (Konica-Minolta and