Meade Instruments 50 AZ-T - Manual (Page 11)

4 . Use "fast" films (high A S A ratings) to reduce exposure
t i m e s .
5. Focus the image with extreme care. While observing the
celestial object through the camera's viewfinder, turn the
telescope's focus knob to achieve the sharpest possible
focus.
6. Hold a piece of cardboard over the front of the telescope
until the shutter has been locked open and all vibrations
have had time to dampen out.
7. Bracket exposure times widely. Correct shutter speeds vary
widely, depending on lighting conditions and the film used.
Trial-and-error is the best way to determine the proper
shutter speed in any given application.
8. Terrestrial photography through a telescope is sensitive to
heat waves rising from the earth's surface. Long distance
photography is best accomplished in the early morning
hours, before the earth has had time to build up heat.
9. NEVER attempt to photograph (or observe) the Sun.
Astrophotography is an acquired skill; exercise patience and
expect to waste a few rolls of film as you learn the techniques.
The rewards of taking a quality astrophotograph, however, will
make all your efforts worthwhile.
OPTIONAL ACCESSORIES
A wide assortment of professional Meade accessories are
available for the 16" Starfinder Equatorial Telescope.
Basic Camera Adapter: A Basic Camera
Adapter is necessary for photography
through a Starfinder Equatorial. A n
eyepiece can be inserted into the adapter
and an enlarged image is projected onto
the camera film plane.
Dust Cover: This snug-fitting vinyl dust cover protects optics
from outside dust during storage of the telescope.
Eyepieces: Many additional eyepieces are available for higher
and lower magnifications. All Meade Starfinder Equatorial
telescopes accept standard 1.25" O.D. eyepieces as well as 2"
O.D. eyepieces.
Meade Super Plössl (SP), Super Wide Angle (SWA), and Ultra
Wide Angle (UWA) Eyepieces in the standard American-size
(1.25") barrel diameter (Fig. 9) or the 2" barrel size permit a wide
range of magnifying powers with the telescope. Powers
obtained with each eyepiece are as follows:
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ASTROPHOTOGRAPHY
Your reflecting telescope can be used as a powerful
astrophotographic lens with the addition of virtually any 35mm
Single Lens Reflex (SLR) camera body.
The Basic Camera
Adapter (see OPTIONAL ACCESSORIES, this page) and T-
Mount for your specific brand of SLR camera serve as the link
between telescope and camera.
The Starfinder Equatorial Telescope design allows the user to
take short exposure photographs of the Moon and planets using
either prime-focus or eyepiece projection photographic
techniques. Designed without slow-motion controls, the
Starfinder is not capable of taking the long exposures required
for deep-sky astrophotography. However, with the purchase of
the optional Magellan II Computer Correction System (see
OPTIONALACCESSORIES, page 12), which includes dual-axis
drive correction capabilities, the ability to guide for longer
exposures is much improved.
To mount a camera on the telescope:
1. Remove the standard lens from your camera and set it
aside. (Remember: the telescope is the camera's lens.)
2. Attach the appropriate T-Mount to your 35mm SLR camera.
3. Thread the prime-focus section of the Basic Camera
Adapter (optional) into the front of the T-Mount now attached
to your camera (Fig. 15).
4. Remove the eyepiece from the focuser and insert the
chrome barrel of the camera adapter into the focuser
drawtube. (Re-balancing may be necessary.)
5. Focus the camera by looking through the camera viewfinder
and turning the telescope's focuser knobs until the image is
sharp.
Fig. 15: Prime-Focus Photography.
Fig. 16: Eyepiece-Projection Photography.
In the above configuration, the telescope is operating in the
"prime-focus" or no-eyepiece photographic mode. When higher
magnification is desired, such as during lunar and planetary
photography, an eyepiece may be inserted into the Camera
Adapter (Fig. 16) so that the image is projected through the
eyepiece, onto the film plane. This is known as Eyepiece-
Projection photography.
A few tips on astrophotography:
1. The telescope must be polar aligned, as discussed above.
2. The mount must be on a solid level surface.
3. Use a cable-operated shutter release. Touching the camera
body to initiate shutter operations will almost certainly
introduce undesirable vibrations.