Minolta XD - Page 17

14
7-3. Acute matt
W Brightness of acute matt
(Brightness)
10074
Micro-prism
ane Acute matt fe a
Ege Conventional matt
50
Pa ey
T T T T 1
1.4 2 2.3 4 5.6 8 ll 16 (F No.)
This is a special matt manufactured through a new process developed by Minolta. Extra-
fine cones are regularly arranged over the entire surface of focal plate at 20y intervals.
The angle at the cone bottom is about 15° and the surface of each fine cone is irregular,
and the number of fine cones is approximately 2.5 million in total. Therefore, the acute
matt have 4 big advantages over conventional matts.
1) Compared with a conventional matt, acute matt is brighter and will not be quickly shaded
even if F-number=5.6 or less as in micro-prism.
2) When focused, the scene is clearly seen in good contrast.
3) Even a slight deflection causes the scene to become obscure, therefore it is easy to focus.
It is easy to focus at any point of the scene because of acute matt over the entire
surface. |
4) Since the matt is very fine, the scene can be observed in detail.
@ Thus, the acute matt is a focal matt which has been designed and manufactured by using
the merits of micro prism (bright, clear and easy to focus) and those of matt surface
(it doesn’t darkens too fast, and the scene is not inharmonious as in micro-prism).