Hasselblad H3D 31MPix - Infrared Focus Set Tings; Focus Aid

7
8
9
12
Focus setting correct
11
Focus setting too close for
the distance of the subject
framed by the central section
in the viewnder
10
Lens focus setting too far
beyond the distance of the
subject framed by the central
section in the viewnder
Depth-of-eld calculation 7
ere are two distance scales (in feet and metres) visible through
the focus distance window on the upper part of the lens barrel.
ere is also a central lens index mark and a depth-of-eld scale.
e focusing distance is read o the chosen scale from the central
lens index.
Depth-of-eld can be calculated as follows:
1. Focus the lens as required.
2. Make an exposure reading (auto or manual) and note the
aperture setting.
3. Find the markings on either side of the central index that cor
-
respond to the chosen aperture.
4. From these two markings, read o on the required lens dis
-
tance scale the two corresponding distances.
5. The depth-of-eld (at that particular aperture and focus set
-
ting) will be the area included between these two distances.
In the example given here, the focusing distance is set at nearly 3
metres. At an aperture of f/22, the depth-of-eld would therefore
extend from just over 2 m to approximately 4.5 m.
Stop down / depth-of-eld 8
A visual depth-of-eld preview can be made by depressing the STOP
DOWN button while viewing the image on the viewnder screen.
Infrared focus settings 9
As infrared rays form an image at a dierent plane to that formed
by visible light, the normal focus settings do not apply. Proceed as
follows in manual focus mode:
1. Focus the lens in the conventional manner until satised.
2. Note the distance setting against the central lens index.
3. Re-align this distance setting against the infrared mark
(coloured red) instead of the central lens index.
Alternatively if you have already calculated the required distance,
you can make a manual distance setting by using the distance
scales together with the infrared mark instead of the central lens
index.
Focus aid 10, 11, 12
As well as the conventional view on the focusing screen to ensure
a sharp image, the H3D also features LED focus aid capability ap-
pearing as two arrowheads to the right of the viewnder display
(except for lenses with a maximum aperture of f/6.7 or smaller).
e arrowheads provide conrmation of a precision focus setting
and are a useful aid when making a setting with eyesight alone.
Manual focus setting
When the le arrowhead alone appears it means the focus setting
is too far beyond the chosen distance (the area framed within the
central zone in the viewnder) and when the right arrowhead
alone appears it means the focus setting is too close. Focus is cor-
rect when both arrowheads appear together. If the focus cannot
be established, then both arrowheads ash.
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