JVC TK-C1481 - Manual (Page 21)

E-21
Back focus adjustment
• With a fixed-focus lens
If the focus can not be adjusted correctly by
rotating the lens focus ring, adjust the back
focus as follows.
1.
Loosen the back focus locking screw by
turning it counterclocckwise (
) with a
screwdriver.
2.
Shoot a pattern closely.
3.
Turn the lens focus ring to
ϱ.
4.
Turn the back focus adjustment ring to
focus at the best point.
5.
Tighten the back focus locking screw by
turning it clockwise (
).
• With a zoom lens
If the image is out of focus when zooming
(telephoto wide-angle), adjust the camera as
follows:
1.
Loosen the back focus locking screw by
turning it counterclocckwise (
) with a
screwdriver.
2.
Shoot a comparatively dark scene with
thin lines.
3.
Set the lens to the maximum telephoto
position, and adjust the lens focus.
4.
Set the lens to the maximum wide-angle
position, and turn the back focus ring to
adjust the focus.
(Repeat steps
3. and 4. two or three
times.)
5.
Tighten the back focus locking screw by
turning it clockwise (
).
Ⅲ Back focus adjustment
Be sure to make back-focus adjustments when changing the lens mounting method or using
a different lens. If required, adjust it as follows:
MEMO
When the subject is bright, the use of an ND
filter permits more accurate back-focus ad-
justment. (The ND filter reduces the amount
of incident light upon the lens equally over
the entire range of wavelength.)
Back focus fixing
screw (M2.6)
Back focus
adjusting ring
Lens focus ring
BF LO
CK
Tighten
Loosen
MEMO
• LENS FOCUS ADJUSTMENT MODE
At the time of focus adjustment, press the
button
at the side of the unit for at least
one second to open the lens iris and to fa-
cilitate focusing. At this time, “LENS FOCUS
ADJUSTMENT MODE” will be displayed on
the monitor screen.
When the adjustment has been completed,
press one of the buttons
to can-
cel focus adjustment mode.
• Focus setting can differ on the color and on
the black and white screen. Make adjust-
ments so that the focus will come to the op-
timum on both screens.