Read your telescope instruction manual for the correct”CleaningprocedurThe Mainto removeMirrorthe”. Nearlymain allmirrordesignscell. Most manuals contain this in the maintenance part
hold the main mirror° apartcellaroundin the thetubetubey’sthreecircumferencescr ws. You. Priorwill tofindanythemremovalne r themarkrearthendpositionof the tube spread 120
of the main mirror cell against the tube with two small sticky labels. Then carefully unscrew these three screws and pull the main mirror cell out of the tube very cautiously.
Now make ’as stencilouter diameterof cardbohards tousingmatchcompassesexactly thatndofscissorsthe main. mirror. The stencil
Cut a hole of 8 to 10 millimeter diameter exactly in its geometrical center.
Place your stencil exactly above the main mirror and copy the inner edge of the small hole directly onto the main mirror with a waterproof marker, resulting in a circle marked on the main mirror
(see next picture).’s center is us
Though often mentioned in the literature, a black spot marking on the main mirrore-
less! You
returned to the.
This circle mark is hidden behind the secondary mirror and therefor has no influence whatsoever on the imaging capability of the primary mirror.
Relocating the primary mirror:
Carefully replace the main mirror cell back into the tube to its previous position using the stickers to locate. Replace screws etc.
The collimation procedure of a Newtonian telescope with pictures.
Step 1
FollowingC llimationpicturesalwaysshowstartsthewithviewa controlfrom theandtubeadjustment’s front endof thedirectlysecondaryonto themirrormain. mirror.
Picture 1 left shows the laser beam (red dot) obviously missing the marker circle in the center of the main mirrror. Note the three adjustment
Hex head screws of° apartthe secondary. Very ca
mirror spread 120u- tiously and only in small steps
While you look directly’sontolightthedotmain mirror watch the laser
moving into the center marker circle while you are adjusting the secon- dary.
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