Lens; Selection; Optical Characteristics; Flange Focal Distance Adjustment - Hitachi HV-C20 Operation Manual

Lens

Caution
Observe the dimensions of the lens mounting
section as illustrated at the right.
If the dimensions are not observed, do not
such a lens, because the lens and the camera will
be damaged.

Selection

1 Optical characteristics

If an appropriate lens is not used, the performance of the camera cannot be fully demonstrated. In
case of a 3-CCD camera using a C-mount lens, the exit pupil of a lens is an important factor.
If the exit pupil is short, colors at the upper and lower parts of the screen become uneven.
Therefore, select a lens having the optical characteristics equivalent to the lenses listed below.
Manufacturer Type
Canon PH10x8RII
Cosrnicar C6ZME
Fujinon D10x8A-MDM21
D12x7.5A-MDM21
When a lens is approaching the fully opened state, picture quality can be impaired by the
deterioration of resolution, and the generation of shading or flare. When the camera is used
with the lens iris opened fully, it is recommended to use a lens for a 3- chip CCD color camera
as listed below.
Manufacturer Type
Canon J7x10B CM AS
Cosrnicar H10ZAME-R
C10ZBME-R
Fujinon S10x8DB-SNDS21
2. Kinds of auto iris lenses An auto iris lens of the video signal (built-in iris amp) type or DC
(Cosmicar's manual override type) can be used. The lens without an iris amp cannot be used.
Some settings must be changed according to the type of the auto iris lens to be used. For settings.

Flange focal distance adjustment

When the picture is out of focus after a lens is replaced, or when the picture is out of focus at
telephoto and wide positions, adjust the flange focal distance by taking the following procedure.
1. In case of fixed-focus lens Set the focus ring of the lens to the infinite position and shoot an object
more than 20 meters away, then rotate the flange focal distance adjustment ring in the direction of N
or F for optimum focus.
2. In case of zoom lens
1) Set the zoom lens to the telephoto position and shoot an object more than 3 meters away.
Then, rotate the focus ring appropriately for optimum focus.
2) Set the zoom lens to the wide position and rotate the flange focal
distance adjustment ring, taking care that the focus ring does not move. Repeat the above steps 1)
and 2) appropriately so that the picture becomes in focus at the telephoto and wide positions.
Lens
Specification
8 to 80mm f1.4
12.5 to 75mm f1.8
8 to 80mm f1.4
7.5 to 90mrn f1.4
Specification
10 to 75mm f2.1
7.5 to 75 mm f1.2
10.5 to 105 mm f1.4
8 to 80mm f1.4
4.2mm or less
Ø18 mm
Flange surface
of a lens
3.8 mm or less
Position of exit pupil(reference)
-118 mm
-40 mm
-138 mm
89 mm
F
N