NATURE & DECOUVERTES Mizar 70/900, User Manual

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USING THE REFRACTING TELESCOPE

WARNING

NEVER USE AN INSTRUMENT TO LOOK DIRECTLY AT THE SUN.

LOOKING  DIRECTLY  AT  THE  SUN,  OR  IN  ITS  IMMEDIATE  SURROUNDING  AREA, 
WILL  CAUSE  IMMEDIATE  AND  IRREVERSIBLE  DAMAGE TO YOUR  SIGHT.  SIGHT 
DAMAGE DOES NOT GENERALLY CAUSE ANY PAIN, AND THE OBSERVER WILL HAVE 
NO  WARNING  UNTIL  IT  IS TOO  LATE.  NEVER  POINT THE  INSTRUMENT,  OR THE 
FINDERSCOPE,  DIRECTLY AT  OR  IN THE  SURROUNDING AREA  OF THE  SUN.  DO 
NOT LOOK IN THE EYEPIECE OR THE FINDERSCOPE WHEN THE INSTRUMENT IS 
MOVING. ANY USE BY CHILDREN MUST BE SUPERVISED BY AN ADULT.

Once the refracting telescope has been set up, the finderscope set and the poles aligned, you are ready 

to start your observations. 

Your refracting telescope will allow you to carry out two types of observations:

Planetary observations: 

The Moon, Mercury, Venus, Mars, Jupiter, Saturn.

Starting your observations of the deep sky:

With several Galaxies, Nebulae...

Note: it will not be of any particular interest to observe a star. Essentially, stars are so far away that 

when seen through a refracting telescope, they look like a simple dot! 

For your first observation, choose something easy to see: The Moon to help you get used to how the 

refracting telescope works and how to use it. 

To achieve the best results during your observations, heed the following advice:

Warning: During all observations, your refracting telescope must remain aligned, so you can benefit 

from the advantages of the equatorial mount.

In order to move the optical tube towards an object to be observed, you simply need to unscrew the 

two brakes (RA) and (Dec) so that the telescope can turn freely, while the right ascension axis conti-

nues to point to the North star.

Once an object becomes visible in the instrument’s field of view, you will simply need to slowly turn 

the right ascension knob (12) to offset the rotation of the Earth throughout the observation.

• To centre an object in the refracting telescope, first use the finderscope to locate the object that you 

wish to observe. Once the object is centred in the reticle of the finderscope, it will appear in the eyepie-

ce of the instrument. (If this is not the case, it means that the finderscope is not set: see how to adjust 

the finderscope) tighten the two brakes (RA) and (Dec).

• Always start an observation with a low-powered eyepiece (for example, eyepiece K 25mm)

• Once the object has been centred, you can align the poles by turning the buttons on the eyepiece 

holder (20). You will note that the celestial body observed starts to slowly move within the field of the