Iso Sensitivity - Leica M9 Instructions Manual

ISO sensitivity

In traditional photography, the choice of the ISO value
reflects the light sensitivity of the film used. Higher
speed films allow faster shutter speeds and/or small-
er 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
effect can be compared to the "graining" that occurs
with highly sensitive films.
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 overex-
posed.
1
The setting is made in / ISO increments, allowing
3
sensitive manual and tailored adjustment of the shut-
ter speed and aperture values to the relevant situa-
tion.
128 / Basic picture settings
As well as the fixed 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
(see p. 136), this considerably extends the range of
the automatic exposure control, specifically by up to 4
aperture stops. However, it is also possible to define
priorities within the function, e.g. for compositional
2
reasons . 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 SET button (1.21) use the
adjusting 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 flash units (always
1
with / s), the function is not available. This function is always
180
active with the snapshot profile (see p. 141).
2
These options are not available in the snapshot profile.
Note:
The list remains visible for around 2 s after you release
the ISO button. Once the list disappears, the set value
1
is applied.
If you set AUTO ISO, you can adjust the function to
match your working methods or your compositional
2
ideas .
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 sen-
sitivity to be used, and/or
– in the Slowest speed sub-menu, select whether
you want to leave it to the camera to ensure shut-
ter speeds that prevent blurring – using Lens
3
dependent , or
– whether you want to specify a particular maxi-
mum shutter speed yourself in the range between
1/125 s and 1/8 s (in whole steps).
If you select Lens dependent the camera only
switches to a higher sensitivity if the shutter speed
1
would fall below the /
Focal length
poor brightness, e.g. speeds slower than
a 35 mm lens.
3
This function requires the use of coded lenses (see p. 110).
threshold due to
1
/ s for
30