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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
