Canon EOS 5D Mark II - EOS 5D Mark II 21.1MP Full Frame CMOS Digital SLR..., Руководство по обслуживанию

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Technical Information
11
３）Focusing screen
The focusing screens are all Precision Matte. The Ee-A standard focusing screen and Ee-D
(with grid) focusing screen have almost the same characteristics as the EOS 20D's focusing
screen. The Ee-S focusing screen, which makes manual focusing easier, is also available.
The focusing screen is interchangeable by using the special tool provided with the focusing
screen.
The Ee-S focusing screen's matte has finer microlenses than the other two types. With
f/2.8 or brighter lenses, the characteristics of the wide-area light distribution angle is
controlled (Fig. 022). The bokeh characteristic for the defocus near the point of focus is
very different compared to the other two types. This makes it easier to see the point of
focus during manual focusing.
Standard Precision Matte Super Precision Matte
Fig. 021 Focusing screen enlargement
1.5 Exposure control
１）Metering
⑴Metering optics and metering sensor
The metering optics has the metering lens and 35-zone
metering sensor (Fig. 023) positioned behind the pentaprism.
For the 9 AF points, the metering lens magnification has
been set to obtain an optimum correlation between the
metering sensor zone areas.
⑵Metering modes
Evaluative, partial, spot, and centerweighted average
metering are provided. Partial metering uses approx. 8% of
the viewfinder area at the center, and spot metering
uses approx. 3.5% of the viewfinder area.
⑶Evaluative metering/E-TTL II algorithm
The basic characteristics of evaluative metering/
E-TTL II autoflash have been adjusted to make them the
same as with the EOS 20D that has the same 35-zone
metering sensor and One-Shot AF with 9 AF points.
Fig. 022 Metering sensor
Fig. 023 Metering zones