Astrophotography; Piggyback Photography - Orion skyView Pro 8 EQ9738 Instruction Manual

9. astrophotography

When coupled to a 35mm single-lens reflex camera, the
SkyView Pro becomes a telephoto lens. To attach a camera,
you need only a T-ring for your specific camera model and the
included camera adapter. First you must attach the included
camera adapter to the SkyView Pro 8 EQ's focuser. To do this,
remove the 1.25" and 2" eyepiece adapters from the focuser
drawtube (Figure 22a). Then screw the camera adapter into
the focuser drawtube (Figure 22b). Now attach the T-Ring to
your camera and thread it onto the camera adapter (Figure
22c).
Use the camera's viewfinder to frame the picture. Use the tele-
scope's focuser to focus the image. You may want to consider
using a remote shutter release instead of the shutter release
on the camera; touching the camera can vibrate the system
and blur the resulting photographic image on the film. Use
the focus lock knob on the focuser to lock the focus when the
image is sharp.
Several different types of astrophotography can be success-
fully attempted with the SkyView Pro 8 EQ.
Moon Photography
This is perhaps the simplest form of astrophotography, as no
motor drive is required. Point the telescope toward the Moon,
and center it within the camera's viewfinder. Focus the image
with the telescope's focuser. Try several exposure times, all
less than 1 second, depending on the phase of the moon and
the ISO (film speed) of the film being used. A remote shut-
ter release is recommended, as touching the camera's shutter
release can vibrate the camera enough to ruin the exposure.
Planetary Photography
Once basic Moon photography has been mastered, it's time to
get images of the planets. This type of astrophotography also
works to get highly magnified shots of the Moon. In addition
to the T-ring, you will need a Universal 1.25" Camera Adapter.
The EQ-3 Motor Drive System (single or dual axis) is also
required. This is because a longer exposure is necessary,
which would cause the image to blur if no motor drive was
used for tracking. The equatorial mount must be accurately
polar aligned, too.
As before, connect the T-ring to your camera. Before connect-
ing the universal camera adapter to the T-ring, an eyepiece
Figure 22a. First remove both the
1.25" and 2" adapters as shown
must be inserted and locked into the body of the universal
camera adapter. Start by using a medium-low power eye-
piece (about 25mm); you can increase the magnification later
with a high-power eyepiece. Then connect the entire camera
adapter, with eyepiece inside, to the T-Ring. Insert the whole
system into the focuser's 1.25" adapter and secure firmly with
the thumbscrew.
Aim the telescope at the planet (or Moon) you wish to shoot.
The image will be highly magnified, so you may need to use
the finder scope to center it within the camera's viewfinder.
Turn the motor drive on. Adjust the telescope's focuser so
that the image appears sharp in the camera's viewfinder. The
camera's shutter is now ready to be opened. A remote shut-
ter release must be used or the image will be blurred beyond
recognition. Try exposure times between 1 and 10 seconds,
depending upon the brightness of the planet to be photo-
graphed and the ISO of the film being used.

"Piggyback Photography"

The Moon and planets are interesting targets for the bud-
ding astrophotographer, but what next? Literally thousands of
deep-sky objects can be captured on film with a type of astro-
photography called "piggybacking". The basic idea is that the
camera with its own camera lens attached rides on top of the
main telescope. The telescope and camera both move with
the rotation of the Earth when the mount is polar aligned and
the motor drive is engaged. This allows for a long exposure
through the camera without having the object or background
stars blurred. In addition to the motor drive (dual-axis), an
illuminated reticle eyepiece is also needed. The T-ring and
camera adapter are not needed, since the camera is expos-
ing through its own lens. Any camera lens with a focal length
between 35mm and 400mm is appropriate.
On the top of one of the tube rings is a piggyback camera
adapter. This is the black knob with the threaded shaft protrud-
ing through it. The tube ring with the piggyback adapter should
be closest to the open end of the telescope tube. Remove the
tube rings from the equatorial mount and swap their position if
necessary. Now, connect the camera to the piggyback adapter.
There should be a 1/4"-20 mounting hole in the bottom of the
camera's body. Thread the protruding shaft of the piggyback
adapter into the 1/4"-20 mounting hole in the camera a few
turns. Position the camera so it is parallel with the telescope
tube and turn the knurled black knob of the piggyback adapter
counter-clockwise until the camera is locked into position.
Figure 22b. Thread the camera
adapter into the focuser drawtube
Figure 22c. The SkyView Pro 8 EQ
with 35mm SLR camera attached
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