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Who was your first ATM mentor?

mirror making ATM beginner
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#1 Get Sirius

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Posted 29 June 2020 - 10:17 AM

Who was your first ATM mentor? 

    Mine was a very unusual man, completely self-taught about mirror making and astronomy.  He was Ernie Brendel, a middle aged farmer in Madison county New York, about an hour from Syracuse.  I met him when I was 13, in 1956, also living on a farm nearby in a very rural area.  I am not sure if he had ever gone to high school.  He became interested in astronomy and decided to make a telescope.  He had almost no knowledge of what had gone before him and did not realize that there were commercial kits for mirror making, like from Edmund. Or books and magazines that would have been useful.  He read somewhere that you could make a curved mirror by grinding two pieces of glass together.  So he wrote to Corning and asked if they could make him two round pieces of glass about 4 inches in diameter and ½ inch thick.  That eventually became his first telescope.  He later reused those blanks and I have them now.  Not actually that round.
     He read that Foucault made mirrors by grinding them together with an abrasive, but it did not say what the abrasive was.  By lots of trial and error he eventually discovered the solution and also the idea of going to progressively finer grades of it.  This self-taught process took years and he plugged away at it as a hobby.  Farmers usually have little time for hobbies.
    Eventually he made a 6 inch parabolic mirror and mastered the knife edge test.  He claims that over the years he made every mistake possible.  When I met him he was working on a 10 inch mirror and he said he thought it might be beyond his abilities.  By that time he knew about Edmund kits and suggested I get the 6 inch one and that he would help me with it.  When it finally came in the mail I could not contain my 13 year old excitement and quickly ran through all the different stages of mirror making in just a very few days, all by myself.   I then proudly showed him my final result – a 6 inch mirror where the outer one inch was only partially ground and polished.  But I couldn’t wait to get it aluminized and use it.  So that’s what we did.  He wisely made no comment about the quality of my work. 
     Ernie was also a rock hound and collected all kinds of mineral samples, which he showed me.  We met at his place several times, not a lot, and he was such a big inspiration to me to go into optics as a profession, which I have been doing as a lens designer for the last 54 years now.   One big regret I have is that I did not ever go back and check in with him when I was an optics major at the University of Rochester, and tell him how much he had inspired me.  At the time I was not aware of it but later I realized that he had been dying for someone like me to come into his life.  He was a small time farmer in a remote area with almost no education but a passion for astronomy and telescopes and absolutely nobody to share that with.  As a self-absorbed 13 and 14 year old I did not realize that I was just as important to him as he was to me.  My takeaway now from this experience is how a mentor can change someone’s life, mainly by example and generosity more than any actual information transferred.
   I have tried to be a mentor professionally to young lens designers whenever possible.  Thank you Ernie for your great example.


- Dave

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Posted 29 June 2020 - 10:53 AM

As a kid, books from the library... Ingalis, Porter, etc. Later, when I joined the local club... Ralph Dakin, George Keene, Ken Brown, Rick Albrecht.    Tom

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#3 CharlieB


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Posted 29 June 2020 - 11:27 AM

Moving this to ATM, Optics and DIY Forum for a better fit.

#4 Don W

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Posted 29 June 2020 - 12:14 PM

Ron Ravneberg from Ohio. Met him at Astrofest in Kankakee, Ill. in the late 80s. He had built a couple of award winning dobs and he helped me build my first big dob. Spent a lot of time on the phone with him during the process. I took my shiny new 17.5" dob to the 1988 Astrofest and won an award for craftsmanship. But the big hit of that event was Dave Kriege's original Obsession 20" dob. His design was so new and innovative that it stole the show.Dave has always been upfront that his scope was the combination of other designs he saw in ATM magazine and other. Dave and I have been good friends since but alas, Ron passed a number of years ago.

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#5 Oregon-raybender


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Posted 29 June 2020 - 12:46 PM

Richard Luce, my grandfather's best friend. Richard was the Director of the telescope making workshop at the Hayden Planetarium in NYC. Mel Roth was the instructor. It was run under the Optical Division of the AAA. I completed my 6 inch mirror while in high school in the late 60's. I became youngest (Life) member of the Optical Division at 16. I was voted in by the committee after passing my knowledge and skill test on optical and machine shop processing. It was a very tough test and took months. Lucky for me I was taking machine shop at high school in New Jersey, which had a great program. I took the 2 year optical technician program at Citrus College under James Kent. 


Very grateful for my mentors, I was able to past on my knowledge to many others over the decades.


Starry Nightswaytogo.gif


From the history of AAA - NYC


Exhibit “B” rules for the Optical Division of the AAA were adopted on October 21, 1937. (Supplementary rules were adopted, June 20, 1945.) Mr. Lou Lojas was first chairman of the Optical Division Supervising Committee. On the Committee were Earle B. Brown, Robert Cox, Ed Hanna, C. Grosswendt and Richard S. Luce. The workshop in the Planetarium had been made available to us.

#6 Pinbout



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Posted 29 June 2020 - 01:02 PM

Delmarva mirror making seminar- all those guys 

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#7 StarmanDan



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Posted 29 June 2020 - 02:15 PM

The late, great, Tom Noe of Teleport Telescope fame. Seeing his beautiful and ingenious creations was an inspiration to many a member of the TAS Dallas club. He hosted the club's ATM meetings in his shop, aka The LTFWT (Largest Telescope Factory in Wylie, Texas) up till he retired and move to Washington state. The Texas Country Reporter even did a segment on him and his scopes.


#8 jgraham



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Posted 29 June 2020 - 02:25 PM

My dad. He was an ATM in the early 1950s and one of the best engineers that I have ever known. Some of my earliest memories are of a 6" f/8 that he made and its ceramic tool. I built my first telescope (a 4.25" f/8) in 1968. 30 telescopes and 30 years later I built my dream scope, a 16.5". I still have his 6" and my 4.25", and I'm in the process of refurbishing my 16.5". T'was a heck of a journey!

#9 Pierre Lemay

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Posted 29 June 2020 - 06:06 PM

My first mentor  back in 1973 was Sylvio Bourgeault. He was an optical technician who worked on fancy optical devices at the National Research Council of Canada (NRC) in Ottawa. He was an acquaintance of one of our neighbors. Since I was getting interested in mirror making I was introduced to him (he lived just a few blocks away). He showed me the basics of mirror making and started me out on a 4 inch. He also supplied me with one or two blanks he had lying around, including a 10 inch pyrex blank which I would eventually turn into an f/6.5 newtonian. I still have the mirror.


I had not spoken to Sylvio in over 45 years. I took a chance and phoned him about two years ago. He was still alive and living at the same house! Unfortunately his health was very bad and he did not want me to come over to meet in person and see him like that. So we chatted on the phone and I got a chance to thank him for starting me out. He passed away a few months later.


IMG_0773 (1).jpeg


The other mentor who played a significant role in my ATM hobby was Fred Lossing. He is the gentleman standing at the right of the picture. I'm that young lad with a full set of hair and a beard. We are looking at an 8 inch fork mounted equatorial tracking telescope I was presenting that year at Stellafane (1981?).


Fred, who among other things was a judge at Stellafane, was a mentor to many of us. He was a senior chemist, also working at the NRC in Ottawa. My high school was just across the Ottawa river from the building where he worked. Fred had a Zeiss grinding machine in his lab and he obtained a special permission for me to be allowed to go into his lab to work my 12.5 inch mirror during evenings and weekends (something that would NEVER be allowed today!).


If Sylvio showed me how to grind and polish mirrors, Fred showed me how to correctly build telescopes. It was a great time to lean mirror making (many people built them in the '70's) and I had the chance to learn from these very generous and experienced mentors.

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#10 Jeff B1

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Posted 29 June 2020 - 06:34 PM

While in the early 1970's  I had made a couple small telescopes; however, it was after meeting Don Parker that my ATM’ing hobby really took off.  That was in 1975 and he “learned’ me much of what I know about the business.  Here he is sometime in the 1970's with his 12.5" f/6:



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#11 ATM57


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Posted 29 June 2020 - 06:35 PM

Sam Brown: All About Telescopes, while stationed in Alaska. Pic: First ATM telescope. 6" F/5 with Meade optics.

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  • First Telescope 6 Inch F5.jpg

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#12 SteveV


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Posted 29 June 2020 - 06:57 PM

Mentor - ATM Listserve.  

Make your Own Telescope - Thompson

Amateur Telescope Making - Ingalls.  

Lots of websites!


Does an archive exist for the ATM Listserve?

Edited by SteveV, 29 June 2020 - 09:54 PM.

#13 Mike I. Jones

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Posted 29 June 2020 - 07:24 PM

Bob Johnston helped me make my first mirror, a 6" f/6,  in 1971 in Corpus Christi.  Bob had made mirrors up to 1 meter in diameter and was an interesting and experienced guy.  I taught myself raytracing from Conrady, "Seven-Place Tables" and ATM3, and followed my interests to Citrus College in Azusa CA in summer of 1972.  There I met Jim Kent, who taught the Optical Technician classes there and was my second mentor.  We made test plates, prisms and optical flats during the day, and were allowed to work on personal projects during the evening.  Great times.

#14 don clement

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Posted 29 June 2020 - 07:34 PM

Clifford Holmes when still in high school. I remember going out to a star party in over Gavilan hills near Lake Mathews back when light pollution and population was way less. Also attended the first RTMC at RCC. Too bad Cliff had Asthma living in smoggy Riverside that killed him.



#15 ckh


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Posted 29 June 2020 - 08:05 PM

The ATM books, Thompson and Howard (circa 1970).



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#16 gnabgib


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Posted 29 June 2020 - 08:46 PM

I  made my first telescope as an 8th grade science fair project using Sam Brown's book.  I placed second in the fair.  It was a 6 inch f/8 reflector.  The part I missed in the book was the inside/outside radius concept when figuring.  Still I could see the "ring" around Saturn (not rings).  About two years later I was introduced to the Telescope Makers Workshop at Chabot Observatory in Oakland Ca.  There I met Paul Zurakowski who ran the workshop. He tested my mirror and declared it a perfect oblate spheroid!.  With his guidance I refigured the mirror to a decent parabola over the next few Friday nights.  I still think highly of Paul even tho I have not seen him for a few years.  The workshop became a central part of my life and still is today.  I even met my wife Debra there. Those who made mirrors at the workshop under Paul's guidance will fondly remember him saying"wellllllllll" as he looked at your mirror under the foucault tester.  The longer the "welllllll" the more work you still had to do!



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#17 kb58


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Posted 29 June 2020 - 08:51 PM

I'd say that it's 90% myself, and 10% my high school physics teacher, who I wish I got to thank for being my best teacher ever. He enlightened me to the stars through his Rocketry and Astronomy club, which sure brought together a diverse mix of personalities!

Edited by kb58, 29 June 2020 - 09:52 PM.

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#18 SandyHouTex



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Posted 29 June 2020 - 08:52 PM

Mr. Blosser.  He was in his 60s and a member of the Stark County Astronomical Society in Canton, Ohio, as I was.  He ran the mirror making classes every Friday night.  He helped me make my first 6 inch f/8 mirror.


I’ll never forget the view when we watched the full Lunar eclipse on April 12-13 1968.  We used a telescope that he made, I can’t remember if it was a 6 inch or 8 inch Newt, and a war surplus Erfle.  The view is still etched in my mind.  He was such a nice person.

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Posted 29 June 2020 - 10:08 PM

Just to mention a few very first ones, but this dfoes not ehaust the listby any means. These are the most influential ones:


Professor Philip Pinches, Optical Division, Hayden Planeteraium, Museum of Natural History, NYC, 1983.  He coached me with my first mirror (a 6" f/6). I was allowed to make an f/6 because I have been studying optics on my own while in medical school, and have written a raytrace program for my Texas Instruments programmable calculator using magnetic programmable cards as program media. The books in particular by Rudolf Kingslake Lens design Fundamentals, and Warren J. Smith's Modern Optical Enginering.


Before I left New York City a coule of years later, Prof. Pinches gave me his old copies of Conrady's Applied Optics and Optical Design (at that time out of print). Later I found out that Kingslake was Conrady's son-in-law. From Conrady, I learned the G-sum method which came in handy years later when writing an articile for the Amateur Telescope Making Journal in the 90's on R. J. Lurie's special case anastigmat using a two element corrector with the first element being a pcx lens and the second a plano concave lens. The curved surfaces had identical radii but opposite sign.


Barry Levin, of Brooklyn, NY, also from the Optical Division, with whom I made my first set of three 10-inch autocollimation flats as a second project after my 6-inch f/6 paraboloid. As soon as I was done with the mirror I knew I would never again use the Foucault test (because autocollimation made so much more sense). Until I made my Bath interferometer almost 10 years ago, I've used only autocollimation for Newtonains ans refractors. 


Al Jaegers, Sr. who indebted a cash-strapped student, with two beautiful 6-inch BK7 blanks after I told him I was planning to make a Houghton telescope but was still saving money for the blanks.


Finally, Paul Weissman,also from the Optical Division,  professionally associated with the Ferrand Optical (still in Valhalla, NY at that time) as an optical engineer there, who was trying to persuade me to go into optics.

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#20 racunniff


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Posted 30 June 2020 - 07:35 AM

Clyde Tombaugh. When I was in high school in Las Cruces, New Mexico, my dad took me to a lecture by Prof. Tombaugh at New Mexico State University. Afterwards, I went up to talk to him. He was very accessible, and at some point I mentioned that I was interested in astronomy and asked him how I could learn more. He said, "build a telescope" and proceeded to give a brief overview of the subject. I was hooked, my parents bought me the Edmund Scientific 6" mirror kit (including the Sam Brown "All About Telescopes" book), and, well, here I am.

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#21 bobruben


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Posted 30 June 2020 - 09:41 AM

My first book mentors were book authors Kriege and Berry. I built my 16 inch Obsession Dob clone circa 2002 with that knowledge.


A bit later, Mike Lockwood held mirror making classes in his basement for a handful of people. He was invaluable in helping me properly measure my 8 inch mirror's figure, and also, later in figuring.

Three or four people would all measure the zone offsets. We would average the results, and then run those numbers. It was fun, and instructive.

A handful of mirrors came out of that class.


I don't think I would have ever finished that mirror without the group's help, especially Mike.

#22 Mike Lockwood

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Posted 30 June 2020 - 01:41 PM

I think out of the group, Bob is the only one so far who has actually finished a telescope to put their mirror in, so well done Bob.


Dick Wessling was a good friend and an early mentor for me.  He helped me get through my first mirror, an 8" f/3.9, via phone calls.  I visited his shop a number of times later on.  I wish he was still around so I could do that again.  I have one of his polishing machines, which John Pratte built for him.

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#23 John Fitzgerald

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Posted 30 June 2020 - 01:47 PM

I ground and polished a 8" mirror to a 70" focal length back in high school in late 1969 or so, with no mentor at all, just an Edmund kit and the available ATM books from the library.  I never mounted it until 1988, when another ATM and I got together and re-ground and figured it down to f/6, along with a couple other mirrors.

#24 mark cowan

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Posted 30 June 2020 - 03:28 PM

As a kid I had a paperback copy of Texereau's How To Make a Telescope which I read through quite a bit, and I had a grit kit from Edmunds, but alas never had enough money for any glass. 


As an adult I took John Dobson's weekly class at WOU that Garth Ellison (sp) in Monmouth sponsored in the mid 90's.  John was the perfect irresistible force to overcome inertia and actually build an 8" from scratch.  The mirror that he approved and I had coated turned out, alas, to be an excellent sphere - once I made a Foucault tester and checked it. I had missed the lesson on parabolizing for some reason I don't recall, but I turned to Texereau (in a nice hard back copy) and wore parts of that book out as well getting it done correctly, as well as ample star testing along the way.


Other guiding lights, really too numerous to mention, were found on the ATM List.  :waytogo:

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#25 Augustus


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Posted 30 June 2020 - 03:39 PM

Dave G and Dan Landis (pinbout) come to mind but I had an enormous amount of help from a lot of other folks on here on my first mirror and scope build.

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