Canon C12-8453, Руководство по обслуживанию

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2) AI Servo AF control from the second frame
As with the EOS-1V, the EOS ELAN 7 E / EOS 30 executes predictive AF by
using statistical calculation and analysis. Also, during continuous shooting,
focusing is executed twice while the mirror goes down once. This improves the
focusing efficiency.
3) Stabilizing the film advance speed
As with the EOS-1V, the EOS ELAN 7 E / EOS 30 provides a standby time after
the lens is driven. This standby time absorbs any irregular lens driving time so
that the continuous shooting speed remains stable.
4) Predictive AF control
The EOS ELAN 7 E / EOS 30's One-Shot AF speed is about the same as the
EOS-3's. The AI Servo AF's predictive focusing performance is also the same as
the EOS-1V and EOS-3's. With an EF 300mm f/2.8L IS USM lens attached, the
EOS ELAN 7 E / EOS 30 can focus track a subject approaching at 50 kph up to
about eight meters away. This was made possible by: 1. An improved AF
algorithm, 2. An improved picture-taking sequence, and 3. A CPU capable of
high-speed processing.
(5) AF Modes
Like the EOS ELAN II E / EOS 50 E, the EOS ELAN 7 E / EOS 30 has three AF
modes: 1. One-Shot AF, 2. AI Servo AF, and 3. AI Focus AF. In the Full Auto and
Programmed Image Control modes, the AF mode is set automatically. In the Creative
Zone modes (except DEP), the user can select one of the three AF modes.
As with the EOS ELAN II E / EOS 50 E, the algorithm used for focusing point
selection during automatic focusing point sel AI Servo AF requires the
subject to be first focused with the center focusing point. The off-center focusing
points remain on standby and if the subject moves from the center focusing point to
an adjacent focusing point, autofocusing continues. When Eye Control is ON in the
AI Servo AF mode, Eye Control Servo AF takes effect. This enables the user to focus
the subject continuously just by looking at the moving subject in the viewfinder.
(6) Focusing point selection
The EOS ELAN 7 E / EOS 30 has
focusing point selection keys on the
Quick Control Dial. The keys make
focusing point selection faster and more
intuitive than with any previous EOS
camera. You first press the focusing point
selection, then press any of the keys.
For details on the effects and operation of
C.Fn-11-1/2 and C.Fn-12-1, see “1.10
Custom Functions.”
Part 2: Technical Information
2-6
Fig. 2-11 Focusing Point Selection Operation
[C.Fn-11-0]
Automatic selection
Extreme
left Left Extreme
right
Top
Bottom
Center Right
Automatic selection
Automatic selection
Automatic selection
Automatic selection
*Pressing the focusing point selector during automatic focusing point selection
enables the selection keys which start from the center focusing point.