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Academic & Professional Books  Reference  Physical Sciences  Cosmology & Astronomy

Collimating a Newtonian Reliably and Scientifically Incorporating the Cave and Laser Telescope Collimators

Handbook / Manual
By: Peter R Clark, FRAS(Author)
120 pages, colour & b/w photos, colour & b/w illustrations
Collimating a Newtonian Reliably and Scientifically
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  • Collimating a Newtonian Reliably and Scientifically ISBN: 9780957645431 Edition: 4 Paperback Mar 2017 In stock
  • Collimating a Newtonian Reliably and Scientifically ISBN: 9781665580830 Edition: 5 Paperback Oct 2020 Usually dispatched within 1-2 weeks
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Collimating a Newtonian Reliably and Scientifically

About this book

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.
     There is nothing axial rotation doesn't perform far more accurately and easily for both low and especially high magnification interests. Adjustment feels micrometre-like with none of the hit or miss that can be endless in the persisting wrong written to look easy advice of fiddling with all the bolts that causes 'Maybe, occasionally and sometimes' to sprinkle most august intuitive approaches. Few have scaled up to the needs of better and faster optics, hardly deviating from what works for the Cassegrain. The instructions developed in this book also put one right on course for correction of the equatorial mount and gyro compass and vice versa where I hail from.   



    One of the various tools for aiding initial alignment can be all that is needed for slow optics and low magnification use. They include the Cheshire Eyepiece, the fascinating Easy Tester 11 and there's a computer program for completing the indoor centring. A Fuji 35 mm film canister does it with a wider and clearer view. Where is the laser collimator? The good news is any laser collimator axial beam when proven accurate by rotating it and used in accordance with these instructions, takes over for the secondary mirror when your black art no longer sets the vertical angle accurately enough – spot on the horizontal axis that before the star test with the Jet Stream somewhere else, only a laser collimator can show. Simple. Enjoy.
   In the event of reliability still remaining elusive, take out the primary mirror and check it's mountings. For some old glued on ones, you should look to the adhesive having failed.

    *..and Reference Handbook by his friend, James Gall Inglis (1864-1939) of Edinburgh. Gall & Inglis were Edinburgh & London publishers of easy access astronomy books to 1960.                                                                                                                                                   


Customer Reviews (3)

  • The instructions work well with good results
    By Peter 2 Mar 2018 Written for Paperback
    "Peter Clark's more scientific technique for Newtonian 'scopes works well and requires just a peephole eyepiece as the only gadget needed. I have used the method on my 6" and 10" telescopes with good results. I do not have either a Cheshire eyepiece or a laser collimator and having seen the latter used can appreciate the risk of an eyeful of laser beam! There is no electronic aid that can substitute for a sound understanding of how a Newtonian is constructed and set up."
    – Christopher Eagleton, Beverley

    Author's notes:
    Christopher's comment about the laser collimator is pretty fair for his two f 5 Newtonians, but by f 3.9 is proving essential for the increasing accuracy in vertical tilt needed by the secondary mirror. Laser collimators do not feature in my instructions until stage[6]. Its beam will then be well within the secondary mirror diameter. Neither big bolt heads nor establishment writer could help the review of a 3.8 on p.94 of Sky at Night Jan 2018.
    3 of 4 found this helpful - Was this helpful to you? Yes No
  • His Cave Collimator works and the book takes over
    By Peter 2 Mar 2018 Written for Paperback
    "I am currently converting old spherical f3 Newise mirrors to paraboloids for putting them into telescopes for wide angle work, using coma correctors. Naturally, collimation will be an issue so we will be making use of your work."
    – Peter Wise

    Author's notes:
    Peter is a recipient of the BAA's Horace Dall Medal for showing marked ability in the making of astronomical instruments.
    1 of 3 found this helpful - Was this helpful to you? Yes No
  • A practical way to collimate your scope
    By Gareth 6 Feb 2019 Written for Paperback
    Peter Wise (of Cape-Newise fame) recommended me to Peter and his book. At first, I was more than a little sceptical that such a simple set of steps could compete with the clear superiority of a ‘modern’ laser collimator and the associated alignment method. Then, after repeated failure with said laser collimation on my Cape-Newise - I could get the spots to line up in all the right places but the views remained terrible - I became desperate and actually sat down and systematically worked through the steps in his book.

    Much to my surprise, I discovered that Peter’s book illuminates some fundamental ‘truths' which seem to have been forgotten and overlooked in our rush to high-tech solutions - once you see them you will kick yourself like I did! Where I had previously languished in screw twiddling 'laser hell’, through applying his method I quickly managed to reliably and accurately set the collimation on my previously impossible to ‘tame' telescope. So if you want to collimate a fast Newtonian or one of their more exotic cousins, then I’d thoroughly recommend a careful read of this book - there really are gems in it!
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At age 15 in 1953 at the Boulevard Nautical School, Hull, Yorkshire, it was noted that I had risen from 13th to 3rd in General Science and remember the extra effort made at home.

The view of the night sky from our back garden led to the Boy Scouts' Astronomy badge. My mother bought me a Norton's Star Atlas, but I had no reason to check out the telescope section until 2014. Astronomy started with Dad's 2” night glasses on variable stars until a pulsating cargo liner on my first voyage ended astronomy for 50 years and I became a Master Mariner. The Decca Navigator wasn't performing well off the Bombay transmitter. The Radio Officer hid behind, 'Nothing to do with Marconi.' As the tanker's Navigating Officer down came chartroom deckhead panels until finding a break in the aerial cable, then 12 years later between ships stumbled into solving TV and radio reception problems, including installing EQ mounted satellite TV dishes, self-employed.

Handbook / Manual
By: Peter R Clark, FRAS(Author)
120 pages, colour & b/w photos, colour & b/w illustrations
Media reviews

"This is a very well researched book."
– Phil Jennings, editor of the BAA Journal

"'The Cave Collimator was excellent for my Maksutov–Newtonian telescope and very good for my Rumak–Cassegrain."
– Professor Ian Morison, Jodrell Bank

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