6
B. If a picture is visible, focus on the picture. If the picture is not
visible, open the iris on the lens. Open the lens as wide as
possible by adjusting the iris ring on the lens for the brightest
picture or by placing the welder’s glass in front of the lens
and forcing the lens to automatically open.
C. When the iris is open to the widest point, re-adjust the focus
for a clear picture. It a clear picture is not possible, set the
focus ring to midrange.
D. Loosen the back focus lock screw.
E. Adjust the back focus ring for a clear picture.
F. Tighten the back focus lock screw.
G. Fine tune the focus with the focus ring on the lens.
H. Remove the welder’s glass from in front of the lens.
I. Adjust the iris of the lens for the best picture quality.
1.7
ZOOM LENS BACK FOCUS ADJUSTMENT
The objective of back focusing a zoom lens is similar to that of a
fixed focal length camera, except that the back focus is also
adjusted to maintain the focus when “zooming” the lens in and
out on a scene.
A. Choose an object at the farthest range that you wish to look
at with a zoom lens.
B. Make sure the iris of the lens is wide open. (Do this by
adjusting the camera at night or use a welder’s glass in front
of the lens.)
C. Adjust the focus to the stop on the far range.
D. Adjust the zoom on the lens to obtain the widest picture.
E. Loosen the back focus lock screw.
F. Adjust the back focus ring for the clearest picture.
G. Tighten the back focus lock screw.
H. Adjust the zoom on the lens to the far telephoto position.
Summary of Contents for KC-2A
Page 6: ...vi TABLE OF CONTENTS...
Page 9: ...2 FIGURE 1 KC 2A CAMERA...
