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Completed in 2014, the journey from adjusting both mirrors at every session for 5 years to just the primary mirror twice a year has been very rewarding, mainly by eventually regarding the Newtonian 'telescope's 45° secondary mirror lateral adjusters as handlebars. Turning them without laying a bike over causes the rider to fall off by inertia. Similarly, adjusting these two bolts results only in distortion of a different shape. Attempts to compensation then follow, whereas the instructions chapter from the 3rd edition keeps one well clear of getting nowhere with fast optics. Support by like minds was found subsequently in Norton's Star Atlas* 11th to 15th editions from 1950 p.50. Then on the internet from around the millennium there's the metalwork of R.F. (Bob) Royce in 'The Ultimate Newtonian,' Conrad Hoffman's secondary mirror 'Taming the dastardly thing,' and in Sky & Telescope Oct. 2010 you'll find Ed Jones's Tracking Travelscope also preventing falling into wrong instructions. They either don't fit the lateral bolts or they lock them into strictly following the axial one, thereby steering instructions into the procedure I have developed independently without metalwork.
The various tools that aid just the initial centring can be sufficient for slow optics and low magnification, and have exclusive benefits, but a film canister EP does it just as well. They include the Cheshire and my Cave Collimator aid for poor lighting, Easy Tester 11, and a computer program completes Dion Heap's Advanced Newtonian Collimation. The good news is any laser collimator's axial beam when proven accurate by rotating it, becomes essential for when black art no longer sets the secondary mirror better than just above or below the horizontal axis. A slightly off focus star magnified 100 × or more will then show any remaining distortion for sorting by stages  to . Do not steer the beam towards the centre. From even further back in time than Norton's and with glass being only nearly a perfect solid, the EELT's mirror is to utilize an adaption of the 18th-century Whippletree mechanism for equalising the efforts of carriage horse teams for countering the variable sag of its segmented mirror and atmospherics.
"'The Cave Collimator was excellent for my Maksutov–Newtonian telescope and very good for my Rumak–Cassegrain."
– Professor Ian Morison, Jodrell Bank