Operation Manual

128 / Basic picture settings
ISO SENSITIVITY
In traditional photography, the choice of the ISO value
reects the light sensitivity of the lm used. Higher
speed lms allow faster shutter speeds and/or smaller
apertures and vice versa, at the same brightness.
The ISO setting on the Leica M9 covers a range from
ISO 160–2500. Optimum reproduction quality is
a chieved with the ISO 160 setting. Higher sensitivities
result in an increasing amount of “picture noise”. This
eect can be compared to the “graining” that occurs
with highly sensitive lms.
The Pull 80 setting has the same brightness as an ISO
sensitivity of ISO 80. However, pictures taken with
this setting have a lower contrast range. When using
this sensitivity setting, you should always make sure
that important parts of the picture are not overexposed.
The setting is made in
1
/
3
ISO increments, allowing
sensitive manual and tailored adjustment of the
shutter speed and aperture values to the relevant
situation.
As well as the xed settings, the Leica M9 also fea-
tures an AUTO ISO function, in which the camera
automatically adjusts the sensitivity to the ambient
brightness. When used with aperture priority mode
1
(see p. 136), this considerably extends the range of
the automatic exposure control, specically by up to 4
aperture stops. However, it is also possible to dene
priorities within the function, e.g. for compositional
reasons
2
. This enables you to limit the range of sensi-
tivities used – e.g. because of the noise mentioned
above, and also to set the shutter speed above which
the automatic increase in sensitivity is activated, e.g.
to reliably prevent blurred pictures.
Setting the function
1. Hold down the ISO button (1.23).
• The possible settings appear in the monitor
(1.32), arranged in a grid.
2. While holding down the ISO button, use the central
setting dial (1.29, forward and back) or the direc-
tion buttons (1.30, by line or column) to select the
desired sensitivity or setting.
1
When setting the exposure manually and using ash units (always
with
1
/
180
s), the function is not available. This function is always
active with the snapshot prole (see p. 141).
2
These options are not available in the snapshot prole.
Note:
The list remains visible for around 2s after you release
the ISO button. Once the list disappears, the set value
is applied.
If you set AUTO ISO, you can adjust the function to
match your working methods or your compositional
ideas
2
.
3. In the main menu (see p. 102/119), select Auto
ISO setup (4.1.5), and
4. Max ISO and/or Slowest speed in the sub-menu.
5. Then, in the Max ISO sub-menu,
– select the range within which you want the auto-
matic function to work by setting the highest
sensitivity to be used, and/or
– in the Slowest speed sub-menu, select whether
you want to leave it to the camera to ensure
shutter speeds that prevent blurring – using Lens
dependent
3
, or
– whether you want to specify a particular maximum
shutter speed yourself in the range between
1/125s and 1/8s (in whole steps).
If you select Lens dependent the camera only
switches to a higher sensitivity if the shutter speed
would fall below the
1
/
Focal length
threshold due to
poor brightness, e.g. speeds slower than
1
/
30
s for
a 35mm lens.
3
This function requires the use of coded lenses (see p. 110).