Swann PRO Serie Manual De Instrucciones página 5

Adjusting Zoom and Focus
FOCUS: The front lever controls the focus (see diagram, opposite).
Adjusting the focus control is kind of like trying on a different pair of glasses - it can make
sharp things look blurry and blurry things look sharp. It's not quite magic, but it's pretty
close.
Basically, once you've set the zoom, twist the focus lever anti-clockwise to loosen the lens
and move the focus lever until what you want to see doesn't look blurry anymore. If you
can't turn the knob any more one way, go back the other way.
You can only have so much in focus at once - photographers refer to the size of the area in
focus as the "depth of field".
The diagram to the lower right shows a couple of different focusing options. The shaded
areas represent the depth of field. As you can see, there is no hard edge, some things are
"more" in focus than others.
Note that this is for illustrative purposes only - there are many factors which contribute to
depth of field which vary from location to location.
Once you have adjusted the camera to your desired setting, twist the lever gently clockwise
until it is firm to stop the lens moving.
Note: At the extremes of zoom (in or out) you may not be able to fully focus the image due
to allowances in the lens mechanism, if this happens simply move the zoom back the other
way a tiny amount to bring the image into clear focus.
A: The lens is at its widest, and focused
on an area relatively close to the camera.
The depth of field is quite large.
B: The lens at its widest with focus set to
"infinity". Anything in the shaded section
will be in focus, and this focus extends to
infinity (that is, things in the far distance
will also be in focus). However, things in
the distance might be too small to see the
detail you require.
C: The lens at its tightest, focused on an
area close to the camera. As you can see,
the more the lens is zoomed, the smaller
the depth of field becomes.
D: The lens at its tightest with focus
further from the camera. At this distance,
the actual depth of field is much larger,
but it doesn't extend to infinity like it does
when the lens is wide.
A
B
C
D
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