104
A
Minimum Shutter Speed
Auto shutter-speed selection can be fine-tuned by highlighting
Auto
and pressing
2
: for example, values faster than those usually selected
automatically can be used with telephoto lenses to reduce blur. Note,
however, that
Auto
functions only with CPU lenses; if a non-CPU lens is
used without lens data, minimum shutter speed is fixed at
1
/
30
s.
Shutter speeds may drop below the selected minimum if optimum
exposure can not be achieved at the ISO sensitivity chosen for
Maximum sensitivity
.
A
Auto ISO Sensitivity Control
When a flash is used, minimum shutter speed will be set to the value
selected for
Minimum shutter speed
unless this value is faster than
Custom Setting e1 (
Flash sync speed
,
282) or slower than Custom
Setting e2 (
Flash shutter speed
,
283), in which case the value
selected for Custom Setting e2 will be used instead. Note that ISO
sensitivity may be raised automatically when auto ISO sensitivity
control is used in combination with slow sync flash modes (available
with the built-in flash and the optional flash units listed on page 311),
possibly preventing the camera from selecting slow shutter speeds.
A
Enabling and Disabling Auto ISO Senstivity Control
You can turn auto ISO sensitivity control on or off by pressing the
W
(
S
) button and rotating the sub-command dial.
ISO AUTO
is
displayed when auto ISO sensitivity control is on.