48
AE- L button 1, 2
This button has two main functions that can be incorporated in
various working methods involving exposure locking. It also has
an extra function for the flash meter capability (see AE-L section
under Flash). The
AE-L
button can:
a) lock an EV setting in manual and automatic modes.
b) be used as a brightness range checking facility in standard
terminology or Zone System terminology.
a) When the button is pressed (fig 1), the light metering facility is
locked to the EV setting at that moment. An
L
(= locked) symbol
appears between the shutter speed and the aperture indication
(fig 2) on the grip LCD and viewfinder LCD to confirm the status.
Press the
AE-L
button again to unlock (toggle function).
In the locked setting, the aperture and shutter speed become in-
terlocked. In this way, a new aperture/shutter combination that
still represents the same EV, can be rapidly chosen. For example,
if you set the shutter at 1/125s and the aperture at f/8 and lock
them together, you can access new EV-equivalent combinations
of, for example, 1/30s a f/16 or 1/500s at f/4 just by moving the
front control wheel.
In practice this means you could, for example, in auto mode, posi-
tion the metering area (spot setting) over an area in the subject
that you determine to be equivalent to a mid-grey and lock it with
the
AE-L
button. You can then recompose the picture with the
metering zone positioned over an area much brighter or darker
while still retaining the original exposure setting and choose a
new combination of aperture and shutter speed settings.
b) The
AE-L
button also allows the spot metering function to make
tonal comparison readings and brightness range checks. When the
AE-L
button is pressed, the metered area is saved as a mid-grey.
When the spot area is then placed over another part of the scene,
the new area is then compared to the saved area and the difference
can be read off the scale seen in the viewfinder. For example, in
a landscape situation you could meter the foreground, lock the
reading with the
AE-L
button (thereby locking that area to be
reproduced as the equivalent to a mid-grey 18%), point the camera
at some rocks to see by how much darker they are compared to the
foreground by the EV difference read off the scale (illus 3).
If you have chosen
Spot
together with
Zone
display (see Custom
options) as well as one of the automatic modes
A
,
S
,
P
or
Pv
, point
the spot marking at an area that you decide should be a Zone 5 and
click the
AE-L
button (illus 4). The meter will now display different
parts of the subject as zone values (illus 5) in the viewfinder LCD,
instead of EV deviations, as you move the spot marking over the
subject. (Included are
Lo
and
Hi
(illus 6)to signify areas beyond
the range of the film).
Alternatively you can choose to re-classify an area as another zone
and then check the rest of the subject to see how other areas fall on
the zone scale. Do this by following the above procedure and then
turning the rear control wheel until you see the new desired zone
value in the viewfinder LCD. You will also see the new exposure
that will now produce that new zone. For example, you might have
measured a rock at zone 5 but wish to make it darker. By moving the
rear control wheel you could re-classify it as zone 4. You will then
be able to see, for example, whether white clouds are now falling
within the exposure range by their new Zone classification.
1
2
6
5
4
3
New metered area is 1.8 EV lower than the area metered
when the AE-L button was pressed.
AE-L button pressed to call the metered area ‘Zone 5’.
Metered area reads ‘Zone 8’.
Metered area beyond film range.
