NPZ TAL-1T User manual

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AMATEUR ASTRONOMER
TELESCOPE ÒÀË -1(TÀË-1Ò)
SERVICE MANUAL

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CONTENTS
Page
1. General directions 3
2. Specifications 4
3. Delivery set 5
4. Design of telescope 6
4.1. Design and principle of operation 6
4.2. Optical train 12
5. Preparation for operation 15
5.1. Telescope assembling 15
5.2. Telescope balancing 15
6. Order of operation 17
6.1. Operation with telescope 17
6.2. Photographic observations 19
6.3. Telescope and atmospheric conditions 20
7. Maintenance 21
8. Possible derangements and methods of their
elimination 22
9. Rules of storage 24
10. Acceptance certificate 25
Supplement. Table of close stellar pairs for testing
image quality of telescope 26
The instrument is subject to continuous development
and improvement, consequently it may incorporate minor
changes in detail from the information contained herein.
12.01

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ATTENTION!
The telescope forms the inverted image like any
astronomical instrument does.
The direct observations of the Sun through the
black light filter are permitted only with the use of
the solar diaphragm.
1. GENERAL DIRECTIONS
The telescope is designed for visual observation of the
celestial objects.
The telescope can operate normally at the ambient temperature from
30°C to minus 30°C.
When buying the telescope one should pay attention to the pack-
age safety ensured by the seal of the manufacturing pliant.
After unsealing the case one should check compliance of the com-
plete set denoted in the list of enclosure. Prior to using the telescope
one gets acquainted with its handling and order off operation.

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2. SPECIFICATIONS
Diameter of primary mirror, mm 110
Primary mirror focal ratio f /7.3
Focal length, 805mm
Magnifications:
-with the eyepiece of f'=25 mm 32x
-with the eyepiece of f'=10 mm 64x
-with the eyepiece of f'=25 mm and Barlow lens 82x
-with the eyepiece of f'=10 mm and Barlow lens 165x
Angular view field of the telescope at magnification:
32x1°29'
64x0°43'
82x0°33'
165x0°16'
Resolution 1.3''
Limiting magnitude 12m
Range of slow-motion control relative to the axes ±4°
Angle of rotation of the telescope in right ascension 360°(24 h)
in declination 360°
Range of setting by latitude 0°-70°
Angular view field of the finder scope 8°
Visible magnification of the finderscope 6x
Minimum distance of observation »65 m
Overall dimensions of the telescope:
length tube 850 mm
height in the operating position 1.650 mm
Mass of the telescope, maximum 20kg

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3. DELIVERY SET
The composition of the telescope and
its delivery set are shown in the table.
Name Qty
Telescope 1
Finderscope 6x1
Eyepiece of f=25 mm 1
Equatorial mounting 1
Support 3*
Pier 1*
Tripod 1*
Hinget clips 2
Accessories and Parts
Eyepiece of f=10 mm 1
Barlow lens 1
Retiñle 1
Yellow light, filter 1
Black light filter (solar) 1
Blue light filter 1
Red light filter 1
Green light filter 1
Neutral (grey, lunar) light filter 1
Blind 1
Bracket 1
Stopper 1
Cap-diaphragm 1
Screwdriver 1
Napkin 1
Screen (for observation of the Sun) 1
Brush 1
Shipping Container
Shipping case 1
Service Documents
Service manual
* The telescope can be completed with a metal pier (TÀË-1) or tripod
(ÒÀË-1Ò)
Table

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4. DESIGN OF TELESCOPE
4.1. Design and principle of operation
The telescope consists of three basic units: the telescope tube,
equatorial mounting and pier with supports.
The tube I (fig. 1) is the basic part of the telescope which embodies
the optical parts: the primary mirror, diagonal mirror, finderscope 3 fixed
in the locating rings 2, eyepieces and Barlow lens which are inserted
In the focusing mechanism 4.
The primary mirror (fig. 3) is mounted in the cell and can be adjusted
by means of the screws I and 2.
The diagonal mirror (fig. 4) is cemented to the cell and fixed in the
telescope tube by means of a spider.
The inlet hole of the tube is covered with the cap 3 (fig.5) after
operation.
The focusing mechanism 4 (fig. 1) is composed of a rack and pinion.
The pinion axle carries the handwheels which help to move the eyepiece
tube. The smoothness of the tube movement can be controlled. For this
purpose the left handwheel is held by one hand and the right handwheel
is rotated clockwise with some effort relative to the left handwheel by
the other hand. The chosen position of the tube can be fixed by the
denoted method if necessary.

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Fig. 1
General view of telescope with metal pier
1
2
3
4
5
6
7

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Fig. 2
General view of telescope with trepod
3
2
1

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The finderscope 3 is the telescope with the magnification of 6 X and
viewfield of 8°.
The equatorial mounting (fig. 6) consists of two axes - the polar axis
2 and the declination axis 6 perpendicular to it.
Fastened on one end of the declination axis is the saddle with the
hinged clips 4 in which the telescope tube is mounted; fastened on the
other end of the axis is the counterweight 8 which can travel on thread
for balancing the telescope. The screen 1 (fig. 5) and the bracket for the
camera 4 can be fastened on the same axis.
The casing of the polar axis is fastened on the bracket 10 with the
scale of latitudes (fig. 6) by means of which the whole system is set to
the latitude of the observers site.
Each axis has a circle which shows an hour angle or declination of
the object visible in the telescope viewfield. The position circle 7 on
the declination axis which shows the declination of the objects fig-
ured from 0 to 90° with a division value of 2°. The circle I on the polar
axis (the circle lot hour angles) is figured from 0 to 24 hours with a
division value of 10 minutes.
The coarse focusing of the telescope tube, relative to both axes is
performed by slackening the clamping screws 3 and by rotation of the
tube relative to the respective axis with the further clamping of the
1
Fig. 3
Primary mirror
Fig. 4
Diagonal mirror
2
1
2

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Fig. 5. Tools and accessories:
1 - solar screen; 2 - cap-diaphragm; 3 - cap; 4 - holder for camera; 5 - Barlow lens; 6 - eyepiece;
7 - light filtes; 8 - screwdriver; 9 - napkin; 10 - blind; 11 - reticle
1234
567
8
91011

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Fig. 6. Equatorial mounting:
1 - circle of hour; 2 - polar axis; 3 - crew of axis brake; 4 - folding
clips; 5 - handwheel of low-motion; 6 - declination axis;
7 - circle of declination; 8 - counterweghts;
9 - hadle; 10 - bracket with cale of latitudes
12109
5
8
7
6
5
4
3

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axes. The fine focusing is performed by means of the micrometer
screws 5 in the range of ±4° relative to the declination and polar axes.
The pier 6 (fig. 1) is composed of tube which is fixed on three supports 7.
The tripod (fig. 2) allows to adjust a height of telescope and to fix
each leg of stops 1 and 2.
The Newton system is used in the telescope. Observations are per-
formed through the tube on which the finderscope is positioned. The
tube axis is set in the required position with the help of the equatorial
mounting.
4.2. Optical train
The reflecting telescope is provided with the Newton optical system
(fig. 7).The parallel beam of rays enters the telescope tube, falls on
the primary mirror 1 with the focal length of 805 mm and, after reflect-
ing from it in the diagonal mirror 3, refracts at 90° and is viewed with
the help of the eyepiece 2.
Optical Train of Finderscope
The optical train of the finderscope is shown in fig.7. The finder-
scope is composed of the objective, reticle and eyepiece.

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Fig. 7. Optical train of telescope:
1 - primery mirror; 2 - eyepiece; 3 - diagonal mirror; 4 - finderscope
1
2
3
4

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Fig. 8. Diagram of setting Barlow lens
Eyepiece
Barlow lens
Eyepiece
Focusing mount
Focusing mount

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5. PREPARATION FOR OPERATION
5.1. Telescope assembling
Before assembling the telescope the units and parts must be cleaned
from the slushing compound of the plant.
The telescope is assembled in the following way.
Three supports provided with captive screws are fixed to the pier
through the holes on its lower end. The equatorial mounting is screwed
on the upper end of the pier. At the same way it is fixed on the tripod.
The polar axis is set by inclining the equatorial mounting by the
scale of latitudes to the observing site and fixed by means of
handle 9 (fig.6).
The telescope tube is mounted on the supports of the saddle and
fixed by means of two clips with the help of hinged screws.
The finderscope should be removed from the mortise of the case
where the accessories are placed, then it should be mounted on the
tube in two rings and fixed by means of six setting screws provided on
the saddle.
For obtaining the required magnification of the telescoped the re-
spective eyepiece or the eyepiece with Barlow lens 5 (fig. 5) is insert-
ed in the eyepiece tube.
5.2. Telescope balancing
For smooth motion of the telescope and reliable operation of the
micrometer screws it is important to balance its movable parts on the
axes of the equatorial mounting. With this purpose the telescope tube
should be set in the horizontal position, the screw of the brake pos. 3
(fig. 6) of the axis of declinations is unscrewed and, holding slightly
the tube by hand, one sees to it whether the tube remains in the
indifferent equilibrium or one of its ends overweights. If the tube is not
in balance, one unscrews the screws of the clips which fix the tube
and moves the tube along its axis until it will be in balance. After that
one screws in the screws of the clips.

It is required to set the axis of declinations in the horizontal position
after unscrewing the brake screw pos. 3 (fig. 6) of the polar axis and,
holding the axis of declinations, to see to it whether the telescope is in
balance about the polar axis. If it is not in balance, move the counter-
weight 8 (fig. 6) along the axis of declinations by rotting it on thread.
When mounting the various devices on the telescope, for
example, the camera, it is required to balance the telescope addition-
ally.

6. ORDER OF OPERATION
6.1. Operation with telescope
Before mounting the telescope, it is required to choose the place
and prepare the site. It must be even and solid. Mount the telescope
on the site and check it for reliable stability.
The telescope has great magnifications and, hence, small view-
fields; therefore, it is provided with a finderscope.
After mounting the telescope, it is required to set parallelism of the
optical axes of the telescope tube and finderscope. For this purpose
one should mount a reticle with cross into the eyepiece f'=25mm. One
should make an adjustment by remoted object. This position of the tele-
scope is fixed by means of the screws of the brakes of the axes.
Then, by operating with the setting screws of the rings 2 (fig. l) of
the finderscope, one brings the chosen remote object to the centre of
the finderscope viewfield. This operation is performed only once. In the
future, before observations only the parallelism of the optical axes of
the telescope and finderscope is checked.
The celestial sphere together with the astronomical objects performs
the visible motion about the celestial axis. Therefore, the telescope is
provided with the equatorial mounting. Being set correctly, this mount-
ing makes it possible to perform the celestial object tracking. After
pointing the telescope to the object, the observer can keep the object
in the viewfield centre for a half an hour by rotating slowly the mi-
crometer screw of the polar axis.
In order to avoid guiding correction in declination, the polar axis of
the telescope should be set parallel to the celestial axis. In this case the
north (upper) end of the polar axis faces the celestial pole positioned
near Polaris (aUrsae Minoris). For visual observations it is enough to
tilt the polar axis at an angle equal to the latitude of the observing site
and to direct it approximately along the line the South - the North. With
such coarse setting of the telescope the object will deviate step by
step in declination (it is lifted or lowered in the viewfield). This error is
corrected at times by means of the micrometer screw of the declina-
tion axis.

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For photographic operations and in the cases when the telescope
can be set stationary, the polar axis of the telescope should be set pre-
cisely. For this purpose one observes any bright star in the East, then
in the South and makes notice to what direction the star is displaced.
If in observation of the star in the East, it is displaced in the tele-
scope viewfield so that in its tracking the upper end of the telescope
tube sinks slowly, the north end of the polar axis should be somewhat
lifted.
If the upper end of the tube is lifted step by step, the north (upper)
end of the polar axis should be lowered.
For precise setting of the axis by azimuth one observes the star near
the meridian circle (above the South point) in the same way. If in the
star tracking one should lower slowly the upper end of the telescope
tube, the north end of the polar axis should be displaced to the West.
If in the process of the star tracking the upper end of the telescope
tube is lifted, the north end of the polar axis should be displaced to the
East.
In 20-30 minutes of such observations one can set the polar axis so
that the star will remain on the cross-hairs for 10-15 minutes without
correction in declination.
After precise setting of, the polar axis one can set the declination
and hour circles which must help to search the objects invisible with a
naked eye or even through the finderscope.
First of all, one should set the hour circle which is rixed on the polar
axis. For this purpose after the fine setting of the polar axis one un-
screws the screw of the brake of the polar axis and sets the declina-
tion axis horizontally. The horizontal setting should be checked with
the aid of a level. After setting of the axis, one sets the hour circle so
that 0 is found against the index. The circle is fixed with screws and
tightened with a nut.
For setting the declination circle fixed on the declination axis one
should find the declination of two-three bright stars in the star cata-
logue or make use of the declinations of the planets given in the astro-
nomical calendar. With thee help of the finder scope one brings the
star or the planet to the viewfield centre of the telescope at maximum
magnification. After that one sets the declination of the required star
against the index. The circle is fastened by means of a screw. Then
one makes attempt to find the second star by its declination. For this
purpose one slackens the screws of the brakes of tile axes and checks
the telescope so that the declination of the sought star is set on the
declination circle. The declination axis is fixed and, by rotating the

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telescope tube slowly clockwise and counter-clockwise around the
polar axis, one brings tile star to the telescope viewfield centre. After
checking of tile circle setting, one tightens it with a nut.
In order to avoid resetting of tile polar axis and circles one should
choose the solid horizontal site. Best of all, it is a concrete section of
l.5xI.5 m size. The position of three supports of the telescope pier
should be marked on this site. The telescope is mounted according to
the marks on the concrete.
6.2. Photographic observations
The complete set of the telescope includes the bracket for a camera
with the help of which one can mount a miniature camera.
For this purpose the bracket is mounted on the axis of declimations
from the counterweight side and the camera is fixed to it with the help
of a captive screw.
The exposures witch are required for photographing the star fields
are tenths of minutes without hindrance of the street lighting. There-
fore, for this period of time one should see to it that the camera follows
the sky precisely in its diurnal rotation. With this purpose the Barlow
lens and the eyepiece with the reticle possessing great magnification
are inserted in the eye piece tube. Near the viewfield centre of the
camera one chooses the bright star to which the telescope is pointed.
To keep the star on the reticle cross-hairs is the problem for an observer
for the whole period of exposure. As the cross-hairs of the telescope is
not illuminated, the image of the guide star should be slightly defo-
cused in order to cross a light circle of the unsharp image of the star by
the cross-hairs and to keep the star in this position for the period of
exposure. For the whole period of exposure one rotates carefully a mi-
crometer screw of the polar axis.One corrects the position of the guide
star by means of the micrometer screw of the declination axis as well
in case of necessity. To obtain the minimum corrections in declination
the polar axis should be set as precisely as possible to the celestial
pole. One should remember that, if the polar axis is set incorrectly,
the images of the stars at the viewfield edges appear as dashes even in
the case when the star image is kept on the cross-hairs.
The bracket makes it possible to use the camera with tile remov-
able objectives, if their mass is not so great.

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6.3. Telescope and atmospheric conditions
At great magnifications together with the increase of the visible
dimensions of the object the disturbances due to atmosphere are
increased. It is expressed in great blurring of the images of the distant
objects, in scintillation of the star images.
The observations in the cold seasons are possible when all tele-
scope parts acquire the ambient temperature. For air circulation inside
the telescope tube there is a hole plugged with a stopper in the cell of
the primary mirror. In operation the stopper should be unscrewed from
the cell.
But in observations the great disturbance of atmosphere may take
place at nights, that leads to bad images of the celestial objects. It is
quite possible that at those nights the observations of the fine details of
the planets and of the Moon are unsuccessful.