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.
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.
ZOOM TELEPHOTO LENS ADAPTATION FOR SINGLE LENS REFLEX CAMERAS WITH REMOVABLE LENS
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35mm
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HOW TO USE YOUR DISCOVERER AS A 1000MM TO 4000MM ZOOM TELEPHOTO CAMERA LENS
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
TO ASSEMBLE
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 Adapter.
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
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
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 camera’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.
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