Eyepiece Projection - Celestron nexstar 5 Instruction Manual

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T-Max 100
T-Max 400
Any 100 to 400 ISO color slide film
Fuji Super HG 400
Ektar 25 or 100
1.
Center the Moon in the field of your NexStar telescope.
2.
Focus the telescope by turning the focus knob until the image is sharp.
3.
Set the shutter speed to the appropriate setting (see table below).
4.
Trip the shutter using a cable release.
5.
Advance the film and repeat the process.
Lunar Phase
Crescent
Quarter
Full
The exposure times listed in table 8-1 should be used as a starting point. Always make exposures that are longer and
shorter than the recommended time. Also, take a few photos at each shutter speed. This will ensure that you will get a
good photo.
If using black and white film, try a yellow filter to reduce the light intensity and to increase contrast.
Keep accurate records of your exposures. This information is useful if you want to repeat your results or if you want to
submit some of your photos to various astronomy magazines for possible publication
This technique is also used for photographing the Sun with the proper solar filter.
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This form of celestial photography is designed for objects with small angular sizes, primarily the Moon and planets.
Planets, although physically quite large, appear small in angular size because of their great distances. Moderate to high
magnification is, therefore, required to make the image large enough to see any detail.
camera/telescope combination alone does not provide enough magnification to produce a usable image size on film. In
order to get the image large enough, you must attach your camera to the telescope with the eyepiece in place. To do so,
you need two additional accessories ; a deluxe tele-extender (#93643), which attaches to the visual back, and a T-ring
for your particular camera make (i.e., Minolta, Nikon, Pentax, etc.).
Because of the high magnifications during eyepiece projection, the field of view is quite small which makes it difficult
to find and center objects. To make the job a little easier, align the finder as accurately as possible. This allows you to
get the object in the telescope's field based on the finder's view alone.
Another problem introduced by the high magnification is vibration. Simply tripping the shutter  even with a cable
release  produces enough vibration to smear the image. To get around this, use the camera's self-timer if the
exposure time is less than one second  a common occurrence when photographing the Moon. For exposures over
one second, use the "hat trick." This technique incorporates a hand-held black card placed over the aperture of the
telescope to act as a shutter. The card prevents light from entering the telescope while the shutter is released. Once the
shutter has been released and the vibration has diminished (a few seconds), move the black card out of the way to
expose the film. After the exposure is complete, place the card over the front of the telescope and close the shutter.
ISO 50
1/2
1/15
1/30
Above is a listing of recommended exposure times when photographing the Moon at the
prime focus of your NexStar telescope.
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ISO 100
ISO 200
1/4
1/8
1/30
1/60
1/60
1/125
Table 8-1
32
ISO 400
1/15
1/125
1/250
Unfortunately, the

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