Camera EOS 20D Digital, Инструкция по эксплуатации

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Autofocus can fail to achieve focus (the focus confirmation light <
o
>
blinks) with certain subjects such as the following:
Subjects difficult to focus
(a) Low-contrast subjects
Example: Blue sky, solid-color walls, etc.
(b) Subjects in low light.
(c) Extremely backlit and reflective subjects
Example: Car with a reflective body, etc.
(d) Overlapping near and far objects
Example: Animal in a cage, etc.
(e) Repetitive patterns
Example: Skyscraper windows, computer keyboards, etc.
In such cases, do one of the following:
(1) Focus an object at the same distance as the subject and lock the
focus before recomposing.
(2) Set the lens focus mode switch to < MF > and focus manually.
1
On the lens, set the focus mode
switch to <MF>.
2
Focus the subject.
¡
Focus by turning the lens focusing
ring until the subject is in focus in the
viewfinder.
When Autofocus Fails (Manual Focusing)
Manual Focusing
Focusing ring
If you press the shutter button halfway during manual focusing, the active
AF point and the focus confirmation light <
o
> in the viewfinder will light
when focus is achieved.
71
The camera has three metering modes: Evaluative, partial, and
centerweighted average metering. In the Basic Zone modes, evaluative
metering will be set automatically.
1
Press the <
Q
> button.
(
9
)
2
Select the metering mode.
¡
While looking at the LCD panel, turn
the <
6
> dial.
q
: Evaluative Metering
w
: Partial Metering
e : Centerweighted Average
Metering
q
Evaluative Metering
This is the camera’s standard metering mode suited for most
subjects even under backlit conditions. After detecting the
main subject’s position, brightness, background, front and
back lighting, etc., the camera sets the proper exposure.
¡
During manual focusing, evaluative metering is based
on the center AF point.
¡
If the subject brightness and background light level are
very different (there is a strong backlight or spotlight),
use partial metering <
w
> instead.
w
Partial Metering
Effective when the background is much brighter than the
subject due to backlighting, etc. Partial metering covers
about 9% of the viewfinder area at the center. The area
covered by partial metering is shown on the left.
e Centerweighted Average Metering
The metering is weighted at the center and then averaged
for the entire scene.
q
Selecting the Metering Mode
N