Bausch & Lomb DISCOVERER 78-1600 사용자 설명서

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CHANGING POWER
To  change magnification, rotate  the  Zoom  Power  Change
Ring  to  the  desired  power  as  indicated  by  the  white
engraved scale.
As you zoom from low power to high power under low light
conditions, you may notice a decrease in image brightness.
This  is  normal. All  magnifying optical  instruments  show  a
decrease in image brightness as magnification is increased.
HOW TO USE YOUR DISCOVERER AS A 1 0 0 0 M M
TO 4000MM ZOOM TELEPHOTO CAMERA L E N S
With  the  addition  of  2  inexpensive  accessories,  the
Discoverer will attach to a 35mm single lens reflex camera
that has a removable lens. It then becomes an integral part of
the  camera’s  optical  system  and  functions  as  an  extra
powerful zoom lens.
The  two  accessories  needed  for  this  are;  a  #22-3030
Telephoto Camera Mount and a Camera Body Adapter that
matches  your  particular  camera  (see  listings  under
accessories at the end of these instructions).
TO A S S E M B L E
1 .
Turn the spotting scope’s Telephoto Adjustment Control
Ring  clockwise  all  the  way  until  it  stops,  then  screw  the
Telephoto Camera Mount over the eyepiece.
2 .
Screw the Camera Body Adapter to the other end of the
Telephoto Camera Mount.
3 .
Remove the standard lens from the camera and attach
the body to the Camera Body A d a p t e r.
TO USE
1 .
Films with the highest ISO ratings are recommended.
The faster the shutter speed, the sharper your picture.
2 .
Mount the spotting scope on a sturdy tripod or shooter’s
stand.  A car  window  mount  is  also  available  but  it  is
recommended that the camera not be operated while the car
motor  is  running  since  the  slightest  tremor  at  even  the
spotting  scope’s  lowest  magnification  can  ruin  image
sharpness. Shield the scope from wind as much as possible
and always use a cable release or the camera’s self-timer to
make an exposure.
3 .
After setting up, locate the subject through the camera’s
viewfinder in the usual way with the spotting scope at it’s
lowest magnification. This gives the widest field of view. Once
located, you can frame the picture as desired with the Zoom
Power Change Ring in the same manner as when using it as
a spotting scope, then use the focusing system of the spotting
scope to bring the subject into sharp focus. Minimum focus
distance as a telephoto lens is 80 feet.
LENS CHARACTERISTICS
Coupling  the  spotting  scope  to  a  camera  creates  a
completely new lens system, the essential characteristics of
which are controlled largely by the scope-with one exception:
the  Discoverer  does  not  incorporate  a  variable  aperture
(f/stop) control. In this new system, each of the scope’s 7
power settings has its own effective f/stop as shown on the
Telephoto Camera Mount, and any increase or decrease in
the amount of light transmitted to the film at any one power
setting  must  be  made  by  a  change  in  the  camera’s
shutter speed.
HOW TO DETERMINE SHUTTER SPEED
The following reference chart can be used for shutter speeds
only under bright, sunlit conditions.
If  your  camera’s  shutter  speeds  do  not  match  these
calibrations and if the difference is very slight, the next higher
speed  indicated  on  your  camera’s  dial  should  be  used.
Underexposure  in  both  black  and  white,  and  color  film
(particularly color film) is recommended.
CAMERAS WITH BUILT-IN METERING SYSTEM
Set the camera’s film speed dial to the ISO rating of the film
being used. Turn the Zoom Power Ring on the spotting scope
to the desired magnification (telephoto effect) and check the
chart printed on the Telephoto Camera Mount for matching
f/stop, determine the shutter speed in the usual way.If the
c a m e r a ’s meter will not give a reading, increase the film’s ISO
setting until it does. Remember to make a note of this higher
setting - the laboratory will need to know it when you bring in
the film for processing. Also keep in mind that all subsequent
pictures on the same roll must be taken at this same ISO
rating - roll film cannot be processed by individual frames.
Spotting Scope/Telephoto
Adjustment Control
Telephoto
Guide
Telephoto
Camera Mount
Camera Body
Adapter
35mm
SLR
Camera
ZOOM TELEPHOTO LENS ADAPTATION FOR SINGLE 
LENS REFLEX CAMERAS WITH REMOVABLE LENS
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