Konica Minolta SLR manual Quality of the viewfinder, Quality of the macro-flash

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

COLOUR

FIGURE

(Jan 20 2003)

(a) (b)

Figure 2 (a,b) Depth of field at aperture 4 and 32; please note variation of focus on teeth

19:17:06	Rev 7.51n/W
11/7/06	369598 -
Journal of Orthodontics JOR3338.3d	The Charlesworth Group, Wakefield +44(0)1924

the original computer generated color using ‘SpyderPRO’ by ColorVisionTM (U.S.). The images were also ‘anonymised’ and assessed by two operators (F.M. and D.B.) for color reproduction. Neither of the assessors were color blind.

Quality of the viewfinder

Quality of the viewfinder was tested	without	a
lens attached. The dioptre correction dial	was set	to

0.This corrector allows long- or short-sighted photographers to avoid the use of correction aids, such as glasses, by correcting the dioptre directly at the viewfinder. For operators not needing any visual correction a setting other than 0 may lead to a smaller or larger appearance of the image shown in the viewfinder.

Two bodies were held simultaneously against the right and left eye of the examiner; the backdrop consisted of five fluorescent light tubes. The cameras were then swapped around to avoid eye dominance distorting the findings. Two operators (R.A. and D.B.) ranked the viewfinders for size and brightness independently, and the consistency was 100%.

Quality of the macro-flash

A manual stopwatch was used to measure the time needed to recharge the macro-flash between two exposures (precision 1/10th of a second). This was after the flash was initially charged and ‘tested’ with an empty exposure. Two measurements were taken and the mean calculated. It was also recorded whether the flash was powerful enough for extra-oral exposures. Each unit

COLOUR

FIGURE

(a) (b) (c)

Figure 3 (a–c) Simulated intra-oral images