This new “azimuth” motion is called Right Ascension (R.A.). In addition, the mount swivels North (+) and
South (-) from the Celestial Equator towards the celestial poles. This plus or minus “altitude” from the
celestial equator is called Declination (Dec.).
Now, consider pointing the telescope to the western or eastern horizon. If the counterweight is pointing
North, the telescope can be swiveled from one horizon to the other around the Dec. axis in an arc that pass-
es through the NCP (any Dec. arc will pass through the NCP if the mount is polar-aligned). It can be seen
then that if the optical tube needs to be pointed at an object north or south of this arc, it has to be also
rotated around the R.A. axis.
Pointing in any direction other than due North requires a combination of R.A. and Dec. positions.
Telescopes with long focal lengths often have a “blind spot” when pointing near the zenith, because the
eyepiece-end of the optical tube bumps into the mount’s legs. To avoid this, the tube can be very carefully
slipped up inside the ring clamps. This can be done safely because the tube is pointing almost vertically, and
therefore moving it does not cause a Dec. balance problem. It is very important to move the tube back to
the Dec. balanced position before observing other sky areas.
Something which can also be a problem is that the optical tube often rotates so that the eyepiece, finder-
scope and the focusing knobs are in less convenient positions. The diagonal mirror can be rotated to adjust
the eyepiece. However, to adjust the positions of the finderscope and focusing knobs, loosen the tube rings
holding the telescope tube and gently rotate it. Do this when you are going to observe an area for while, as
it is inconvenient to repeat every time you briefly go to a new area.
Finally, there are a few things to consider to ensure that you are comfortable during the viewing session.
First is setting the height of the mount above the ground by adjusting the tripod legs. You must consider the
height that you want your eyepiece to be, and if possible plan on sitting on a comfortable chair or stool.
Very long optical tubes need to be mounted higher or you will end up crouching or lying on the ground when
looking at objects near the zenith. However, a short optical tube can be mounted lower so that there is less
movement due to vibration sources, such as wind. This is something that should be decided before going
through the effort of polar aligning the mount.
Camera adapter
To attach a camera to your telescope you may need an adapter to get the camera focused. Some reflectors
require wider motion range than the one allowed by the focuser; some refractors are designed to be used
with diagonal mirrors and thus need a longer focal length when used with camera.
To achieve that, simply attach an extender to the focuser of your telescope and then attach the camera
with a T-adapter to the extender.
16
Specifications
Levenhuk Skyline
120х1000 EQ
Levenhuk Skyline
130х900 EQ
Levenhuk Skyline
90х900 EQ
Levenhuk Skyline
70х900 EQ
Optical design
reflector
reflector
refractor
refractor
Aperture
120 mm
130 mm
90 mm
70 mm
Focal length
1000 mm; f/8.8
39.37”; f/8.8
900 mm; f/6.9
35.433”; f/6.9
900 mm; f/10
35.433”; f/10
900 mm; f/12.9
35.433”; f/12.9
Highest practical power
230x
260x
180x
140x
Limiting stellar magnitude
12.2
12.5
11.8
11.2
Resolution threshold
1.2 arcsec.
1.1 arcsec.
1.5 arcsec.
1.9 arcsec.
Eyepiece
1.25”; SUPER10 &
SUPER25
1.25”; SUPER10 &
SUPER25
1.25”; SUPER10 &
SUPER25
1.25”; SUPER10 &
SUPER25
Finderscope
5x24
6x24
6x30
6x24
Mount
EQ1
EQ2
EQ2
EQ1
Tripod
aluminum;
710-1230 mm
27.953” — 48.425”
aluminum;
700-1250 mm
27.953” — 49.213”
aluminum;
700-1250 mm
27.953” — 49.213”
aluminum;
650-1200 mm
25.591” — 47.244”
