Nathan F
sage
Reged: 10/10/08
Posts: 223
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In your opinion, what top five mirror makers consistently make the best primary mirrors, regardless of cost? Which of the five do you rank as the very best?
I'm most interested in hearing from those with experience testing multiple mirrors in a systematic, scientific manner, rather than anecdotal evidence about singular mirrors from personal scopes, brief views had at star parties, or popular opinion.
Looking forward to seeing whatever one has to say!
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12 inch f/5 Deep Space Observer Dob
31mm Nagler, 13mm Ethos, 1.6x Antares 2 inch Barlow
Celestron SkyMaster 15x70 Binoculars
Homemade Maple Parallelogram Binocular Mount
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llanitedave
Humble Megalomaniac
Reged: 09/26/05
Posts: 12942
Loc: Amargosa Valley, NV, USA
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It will be interesting to see how many folks here have had enough different mirrors to pick out a top five batch.
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"Since the process of science generates more mysteries than it solves, I predict that we'll never learn everything: and we'll continue to generate new ignorance at the speed of knowledge."
"S.O.E." (Sauron's Other Eye), with 16" Royce conical mirror: A permanent work in progress.
10" Homebuilt dob, old Coulter mirror
Under Construction: The "Eye of Sauron" Observatory!
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Mike I. Jones
Carpal Tunnel
Reged: 07/02/06
Posts: 1572
Loc: Fort Worth TX
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Carl Zambuto figured the two 18" f/8 fused silica primaries for the new McDonald Observatory Wren-Marcario Accessible Telescope (WMAT). I tested one in my shop and found the figure to be extremely smooth, with an essentially perfect diffraction ring, and the Foucault and wire test numbers coming in at the 1/25 wave RMS range. I didn't test the other primary, but the data sheet indicated a similar degree of correction. A lot of us have made a few personal mirrors equal to this precision, but not consistently to this precision by the thousands for commercial sales as Carl has achieved. I would put Carl up there among the best in the world. John Hudek at Galaxy Optics and Paul Jones are also up there with Carl.
Mike
Mike
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56 mirrors, lenses, 16" f/6 Newt, 6" f/10 refractor, TOA-130S, Tinsley 5" f/15 Mak, 6" f/4 RFT, Coronado PST. Still to build: 24" f/10 Modified Dall-Kirkham, 10" f/26 Mak, 8" f/12 apo, spectrohelioscope, Herrig, Schupmann, and others.
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dave b
Post Laureate
Reged: 05/10/05
Posts: 3547
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our club has tested hundreds of mirrors, without a doubt, zambuto is the best example in every size.
other mirror makers sometimes make good mirrors, but other times release junk you cant believe even an amateur would call finished - let alone claim to be strehl .995
because of this, i cant even give a top 5. once you let a bad optic "slip" out with sham paperwork, you are forever tainted.
every mirror from kennedy i have seen has been great, but we have not had enough samples yet to put him up there with zambuto. ask again in 5 years maybe.
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dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
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polaraligned
sage
Reged: 12/26/08
Posts: 233
Loc: P. R. of New Jersey
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If you want to go big (22"+) and sub f/4, I know of no body capable besides Mike Lockwood and Steve Kennedy. Kennedy having the edge as he has produced probably more sub f/4 large mirrors than anyone else. Unfortunately, he does not do custom orders and do substrates other than monolithic pyrex. Hopefully that will change soon.
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davidpitre
Carpal Tunnel
Reged: 05/10/05
Posts: 1825
Loc: Central Texas
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Quote:
Carl Zambuto figured the two 18" f/8 fused silica primaries for the new McDonald Observatory Wren-Marcario Accessible Telescope (WMAT).
Mike
Mike. What is that? I haven't heard of it.
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David
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Nathan F
sage
Reged: 10/10/08
Posts: 223
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I was expecting a heated debate! Where is the drama? The intrigue? 5 posts is it? 
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12 inch f/5 Deep Space Observer Dob
31mm Nagler, 13mm Ethos, 1.6x Antares 2 inch Barlow
Celestron SkyMaster 15x70 Binoculars
Homemade Maple Parallelogram Binocular Mount
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Chris Curran
scholastic sledgehammer
Reged: 06/14/05
Posts: 827
Loc: Brandon, FL
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I'm most interested in hearing from those with experience testing multiple mirrors in a systematic, scientific manner,
You're not going to get that here. If you really want to trust this info, save up some cash, buy a bunch of mirrors and submit them to your favorite optical lab for testing. Saving that, you're going to have to put up with anecdotal evidence about singular mirrors from personal scopes, brief views had at star parties, or popular opinion. 
My vote is Royce. Royce Conical mirrors are equal in performance to anything else you can buy, and they have a unique and brilliant mounting method to boot.
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cheers & beers,
Chris
Homepage | Over 40?
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polaraligned
sage
Reged: 12/26/08
Posts: 233
Loc: P. R. of New Jersey
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Quote:
I was expecting a heated debate! Where is the drama?
That is exactly why nobody is posting.
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Mark Harry
Post Laureate
Reged: 09/05/05
Posts: 3128
Loc: Northeast
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It's expected to remain civilised as per the intent of the TOSS.
I've tested a carload of mirrors 14" and under. In retrospect, my testing regimen is very reliable, as long as I'm the one using the rig. I'm the only set of eyeballs I personally trust. I spot things others miss completely; even on interferometric reports.
Short of buying a mess of mirrors as Chris mentions, maybe you should choose someone who can test reliably; and have them take a peek at what you want to buy???????
I've also tested quite a few mirrors, free of charge. Just include return shipping. If interested, PM me.
Mark
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So many projects, so little time!
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Sean Cunneen
Let Me Think
Reged: 08/01/07
Posts: 1226
Loc: Blue Island Illinois
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Try a thread like this in the refractor forum if your after excitment. The names brought up here fit what I would think should be included with the exception of Discovery which from my personal experience makes a very good mirror. Of course there is only one Discovery mirror, it just gets passed around a lot, hence all the long waits.
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Sean Cunneen
Blue Island, IL
12.5" Ultralight Strut Dob
127mm f/9 refractor
35Pan, 10XW, 5XO
Member of the Calumet Astronomical Society
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Chris Curran
scholastic sledgehammer
Reged: 06/14/05
Posts: 827
Loc: Brandon, FL
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cheers & beers,
Chris
Homepage | Over 40?
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davidpitre
Carpal Tunnel
Reged: 05/10/05
Posts: 1825
Loc: Central Texas
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I would put John Hall of Pegasus up there with the best.
I've used quite a few of his mirrors in the field and have never seen even one that was less than excellent+ . I'd say the same of Carl Zambuto. I can't think of anyone else I could say that of, though that is not to put any other makers down. ' just my personal experiences.
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David
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bbasiaga
professor emeritus
Reged: 05/10/06
Posts: 724
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I have a nice discovery mirror, though I have not had it tested. I will say I got it ahead of schedule, no problems at all.
I went with Swayze for my current project. I've looked through several scopes made with his mirrors here, and they are awesome.
-Brian
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Vixen 80EDSF
Stellarvue 102ED2
Orion Atlas 11 EQ-G
15" Astrosystems Telekit w/ Discovery Optics
Lust for something Larger
Lust for something Larger than that
Past Lovelies:
Oberwerk 20x100 binocs
Meade AR5
Meade LX10 8" SCT
All sold to a good home
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roscoe
super member
Reged: 02/04/09
Posts: 192
Loc: Northwestern Mass
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Another vote for Steve Swayze, or at least a certification that he is an honest mirror man...........I bought a miror used, had the seller ship it direct to him for evaluation. and he called to tell me that in current condition, it was best as a doorstop. He could easily have said "good enough", sent it out to be recoated, and sent me a bill. I have observed with Royce mirrors, they sure seemed to do their job well!!!!
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Gert
member
Reged: 04/15/08
Posts: 33
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Hi All,
Please consider Zeiss and Perkin Elmer as well. For a Price they will do what ever you specify.
Clear Skies,
Gert
Edited by Gert (06/25/09 09:56 PM)
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Jeff Morgan
Carpal Tunnel
Reged: 09/28/03
Posts: 1987
Loc: Prescott, AZ
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Good luck. Most people buy from a single supplier until that supplier lets them down. For example, I am on my fourth Royce mirror, and #5 will also be from Royce. He has not given me even the slightest room for doubt, misgiving, or buyers remorse. Add to that the conical is a great concept.
Bottom line, very few people will have a large number of samples from a large number of suppliers. Since people tend not to "churn", that speaks well for all of the known premium suppliers.
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Jeff Morgan
Prescott, AZ
Wile E. Coyote School of Telescope Making
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Mike I. Jones
Carpal Tunnel
Reged: 07/02/06
Posts: 1572
Loc: Fort Worth TX
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I don't want to hijack this thread but I'll mention this briefly.
Installation of the WMAT optics is underway this week and next. First light was this evening, and the images were spectacular through both the north and south mirrors Carl figured for us. Many more pictures to come once the installation is complete.
WMAT is presently the only two-mirror Pfund telescope in the world. The central 24" diameter perforated flat is mounted on an alt-azimuth tracking mount, and feeds either the north or south 18" f/8 paraboloid selected, thus giving full sky coverage.
The WMAT website has been updated. Check it out at
http://idisk.mac.com/rwren/Public/wmwat2/index.htm
Bill should be putting up the newest installation pictures over the next few days there.
I did the optical design for WMAT way back in 2005-6, so it's really exciting to see it finally come together in real hardware. The huge custom 2" binoviewers are going to really knock everyone's socks off.
Mike
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peleuba
sage
Reged: 12/01/04
Posts: 292
Loc: Southern PA
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Quote:
Good luck. Most people buy from a single supplier until that supplier lets them down. For example, I am on my fourth Royce mirror, and #5 will also be from Royce. He has not given me even the slightest room for doubt, misgiving, or buyers remorse. Add to that the conical is a great concept.
This is exactly the reason I purchase only Zambuto mirrors; I've owned six of his mirrors of various apertures. I've gotten to know Carl over the years and he has never let me down. I have not purchased other's glass, because I've never had a reason to look elsewhere.
Consistent excellence is a wonderful thing and a great customer retention tool.
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Paul Leuba
TEC160FL #025
StarMaster 14.5 goto/track
Portaball-8
Canon 10X30 IS Binocs
Sets of Nagler T4's, T5's, T6's, TAK LE's, TV Plossls
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NHRob
Post Laureate
Reged: 08/27/04
Posts: 3159
Loc: New Hampshire
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Zambuto
Royce
Swayze
Spooner
John Hall
Do I have to stop at 5?
Rob
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Rob
**********************
Canon 12x36 IS binos
TEC-140: #433 on CGEM
Faworski orthos (7,10,16.7mm)
stuff ...
no free time ... lots of clouds !
" Life is what happens to you while you're busy making other plans" !!
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Jeff Morgan
Carpal Tunnel
Reged: 09/28/03
Posts: 1987
Loc: Prescott, AZ
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Awesome concept Mike. What kind of abberation or effects are introduced by the central perforation? Does it act just like a secondary obstruction in a conventional Newtonian?
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Jeff Morgan
Prescott, AZ
Wile E. Coyote School of Telescope Making
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skywatchbob
newbie
Reged: 06/20/09
Posts: 1
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Here in Chicago is Dan Joyce. What he will do is guide you through the mirror making experience. You will come away with an excellent mirror. Otherwise, if you get a Dan Joyce mirror you will have a mirror that is among the best.
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ausastronomer
scholastic sledgehammer
Reged: 06/30/03
Posts: 937
Loc: NSW Central Coast (Australia)
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Quote:
Zambuto
Royce
Swayze
Spooner
John Hall
Do I have to stop at 5?
Rob
That is limiting your choice of opticians to CONUS. There are some excellent mirrors made outside of CONUS. Peter Ceravolo in Canada and Mark Suchting in Australia spring immediately to mind. I am sure there are also some outstanding opticians in Europe, Great Britain and Japan, all of whom could produce mirrors of equal quality to those you have listed.
Limiting your choice to US based opticians, I would probably agree with your choice, although to be honest my 18" OMI mirror is excellent and with it I am clearly seeing limited and not optical quality limited, having had it to 1050X on the moon on several occasions under ideal seeing conditions.
Cheers,
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John Bambury
AS of NSW
AS of Hunter Valley
18"/F4.5 Obsession fully loaded with OMI optics
14"/F4.5 SDM fully loaded with Zambuto Optics
10"/F5 Newtonian with Argo Navis
Lots of Pentax XW's. 12mm & 17mm Nagler T4's, 31mm Nagler T5 & 13mm ETHOS. TV Paracorr and 1.8X TV Barlow and 2.5X TV Powermate
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polaraligned
sage
Reged: 12/26/08
Posts: 233
Loc: P. R. of New Jersey
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It is a little more complex than this. Opticians tend to specialize in size ranges and focal ratio's.
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GJJim
scholastic sledgehammer
Reged: 09/09/06
Posts: 907
Loc: Western CO
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Quote:
That is limiting your choice of opticians to CONUS. There are some excellent mirrors made outside of CONUS. Peter Ceravolo in Canada and Mark Suchting in Australia spring immediately to mind. I am sure there are also some outstanding opticians in Europe, Great Britain and Japan, all of whom could produce mirrors of equal quality to those you have listed.
Not to sound too parochial, but I think this thread is focused on opticians who sell large parabolic mirrors to amateurs in the U.S. market. AFAIK, Ceravolo stopped making amateur optics many years ago. I'm sure the others you mentioned make fine mirrors, but few have ever heard of them.
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jim molinari
member
Reged: 02/02/08
Posts: 19
Loc: California
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No. I'll recommend John Lightholder.
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Jim
20" Spica Eyes Slipstream
11" SCT/Modified Sirius EQ-G
180mm MCT/ASGT
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polaraligned
sage
Reged: 12/26/08
Posts: 233
Loc: P. R. of New Jersey
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Well the original poster says regardless of cost.
The Ion-Milled optics by Aries may be the best in the world. I think that is all that RCOS is using now.
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AlienFirstClass
professor emeritus
Reged: 02/13/09
Posts: 742
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Quote:
I was expecting a heated debate! Where is the drama? The intrigue? 5 posts is it?
From what I have seen in the past while reviewing the archives of CN, asking this type of question results in the discussion ultimately being closed (censored) by the moderators.
Apparently trying to accurately assess the quality of commercial mirrors is a taboo subject in amateur astronomy.
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gaz-in
sage
Reged: 12/17/07
Posts: 443
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Another vote for Steve's honesty. I recently acquired a Hubble Optics 14 Sandwich Mirror and sent it to him for check out and refiguring (I was assuming given the price I paid it would need touched up). After testing, he responded with a very positive report, said it was a very good mirror, did not need any refiguring (to my surprise), and sent it back to me.
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CHASLX200
Carpal Tunnel
Reged: 09/29/07
Posts: 1812
Loc: Tampa area Florida
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I have owned 5 Zambuto mirrors and two OMI mirros all of them have done well past 1000x. When optics get this good it's just too hard to pick a winner.
Chas
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pstarr
Pooh-Bah
Reged: 09/17/04
Posts: 1280
Loc: NE Ohio
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I think Dick Wessling deserves a mention here. He is right up there with those who were mentioned so far. Dick's web site.
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Paul
10" Home built F-6 Eq Newt. w/Zambuto mirror, built for lunar and planetary viewing.
12'x12' roll-off roof observatory
6" Home built f-6 Newt. w/Dick Wessling mirror on CG-5 Eq. mount, built for high resolution work.
4.5" Orion Starblast on Eq. mount
TV Radians 4,5,6,8,10,12,
Pentax XL 10.5mm
Pentax XW 14mm
Baader Hyperion 17mm
4&5mm UO Abbe Orthos.
3.2mm TMB planetary
TV 2.5x barlow, TV 1.8x barlow
My equipment philosophy... If it ain't broke, fix it anyway.
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Tele
sage
Reged: 11/01/05
Posts: 217
Loc: Eastern Oklahoma
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I am going to give a shout out to Alan Raycraft. My 14" refigured mirror holds its own agianst the competition. Dan McShane's off-axis cookie cutter mirrors deserve praise as well.
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The most exciting phrase to hear in science, the one that heralds the most discoveries, is not "Eureka!", but "That's funny..."
-- Isaac Asimov
14" f4.56 Homemade dob w/ Raycraft Optics
8" f5 Homemade dob w/ Orion Optics
4" f10 Homemade off axis dob w/ DGM optics
10 x 60 Apogee Binos w/ neb filters
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14dobguy
scholastic sledgehammer
Reged: 12/09/08
Posts: 819
Loc: rhode island
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dan i just noticed your post and cant believe steve said that hubble mirror was good and didnt need any refiguring...WOW that excites me,i also have a 14 inch hubble mirror. i guess those guys are getting better over there in china. i expect a "rough hubble" link after this post lol
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Brian
14" dob
sky commander
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gcs111
newbie
Reged: 05/01/07
Posts: 2
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My vote is for Steve Kennedy. I've looked thru and star tested these mirrors he made 22" f4.6, 24" f 4.6 and 4.1...28 f-3.6(three of em) and two 32" f-3.6's. All were to die for. Have also looked thru a few of Carl Zambuto's mirrors....two 14.5's and one 16" , not sure of fl's but they were around f-4. Also to die for. My tests were using relatively high powers and a medium bright star. Both intra/extra focal images were excellent. Steves mirrors have given us, at Mt. Pinos, some of the very best images of any deep sky and planetery objects we've ever seen.
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izar187
sage
Reged: 09/02/06
Posts: 248
Loc: 43N
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Carlos Zapata, one time of Coulter's Tijuana optical shop. Definitely, yep definitely.
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4 thru 13 inch scopes.
30 years observing.
You just read this on the internet, so.....
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ausastronomer
scholastic sledgehammer
Reged: 06/30/03
Posts: 937
Loc: NSW Central Coast (Australia)
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Quote:
I am going to give a shout out to Alan Raycraft. My 14" refigured mirror holds its own agianst the competition. Dan McShane's off-axis cookie cutter mirrors deserve praise as well.
When I was at TSP in 2007 I briefly used Barbara Wilson's 7" Starmaster Oak classic, "Ollie", with an Alan Raycraft mirror; and it was excellent.
Something a little interesting. At TSP in 2007 Al Nagler was there with a couple of his staff. One of Al's staff was "Scott", I can't remember his last name. A nice guy in his late twenties, early thirties at a guess. He brought along a 12" or 12.5" scope which he had built himself and won an award with at TSP. He did the mirror in that scope himself, as well as build the scope. It was without a doubt one of the most superb mirrors I have ever had the privilege to observe with. It was an abolute rip snorter. I am guessing he had a fair instructor on the project, or at least at some time previous 
Cheers,
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John Bambury
AS of NSW
AS of Hunter Valley
18"/F4.5 Obsession fully loaded with OMI optics
14"/F4.5 SDM fully loaded with Zambuto Optics
10"/F5 Newtonian with Argo Navis
Lots of Pentax XW's. 12mm & 17mm Nagler T4's, 31mm Nagler T5 & 13mm ETHOS. TV Paracorr and 1.8X TV Barlow and 2.5X TV Powermate
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txmnjim
member
Reged: 03/31/09
Posts: 26
Loc: Rochester, MN
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I can't mention 5 but I can mention JC Wilkinson, formerly
of Galaxy Optics. Don't know if he's still making mirrors
but he re-figured an 8" for me many years ago and it is one
of the best.
jim
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Keep looking up!
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Bill Cheng
super member
Reged: 05/21/05
Posts: 183
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Dave Groski gets my vote. He has most first place optical awards from Stellafane. I have star tested some of the mentioned top 5 makers and not one is close. Some are good but right away one can see correction problems, and then there are a few I'll be embarrass to put my name on it if I've made it. Most of Dave's I have to look long and hard to see a difference in star testing his scopes. Just my personal observations.
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Bill
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CHASLX200
Carpal Tunnel
Reged: 09/29/07
Posts: 1812
Loc: Tampa area Florida
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Also Dan Joyce makes great mirrors. I have one of his 8" F/6.7 and it is a 10 in my book.
Chas
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alpal
sage
Reged: 06/15/09
Posts: 204
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Have a look at Anthony Wesleys latest mirror.
Bottom of the page
http://www.acquerra.com.au/astro/equipment/Nemesis-16/
I suppose those in the know are all waiting for
the results which - maybe will out perform all
the mirrors stated in this article.
Notice the mirror has a honeycomb hollow structure!
Does this mean that Mark Suchting of Deep Sky Optics
could get the prize for making the worlds best mirrors
for amateur astronomers?
See his web page
http://users.tpg.com.au/masuch/dso/
QUOTE:
"16" Mirror blank, front surface. This surface is 12mm thick and made from fine annealed Borosilicate glass. It has the Radius of Curvature marked (126") from the factory (Newport Glassworks), ie it's currently a spherical surface. This will be reduced to a parabola with FL 64" when it's done.The mirror blank will be handed onto Mark Suchting of Deep Sky Optics for finishing."
QUOTE: Newport Glassworks who makes the blank.
see link:
http://www.newportglass.com/afuscelr.htm
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dave b
Post Laureate
Reged: 05/10/05
Posts: 3547
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that nemesis blank is a sandwich mirror, not honeycomb.
mirrors of that style have been around for a long time, zambuto had made some mirrors like that with blanks that came from a company called stablelite, back in the 90s. hextech was another company that did large sandwich mirrors in that style.
this would be an example of a honeycomb mirror:
http://www.embeddedrf.com/Lookinglass_Webpage_Files/Webbed_Backed/Webbed_Blank.html
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dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
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Brian Engel
member
Reged: 08/25/09
Posts: 93
Loc: Cincinnati,Oh
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Ditto
Quote:
I think Dick Wessling deserves a mention here. He is right up there with those who were mentioned so far. Dick's web site.
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alpal
sage
Reged: 06/15/09
Posts: 204
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QUOTE:Dave B
"that nemesis blank is a sandwich mirror, not honeycomb. "
OK I stand corrected.
I will still be interested in Anthony Wesley's results.
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Bird
Post Laureate
Reged: 08/07/03
Posts: 3024
Loc: Canberra, Australia
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That 16" f/4 mirror has been in the works since January... it took a *long time* for Newport to cast it and get it to me, I received the blank in mid August.
The delivery date for the finished mirror is not yet known, maybe in the next month or so with any luck... as soon as I know how it performs I'll post more info.
The mirror is designed for fast cooling, not only the radial fins and open design but also the array of holes in the back surface where I can blow air in between the front and back.
cheers, Bird
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Deep Sky Optics 13.1" f/5.5 newtonian,
PGR Dragonfly Express, PGR Dragonfly 2
RedHat Linux + Coriander
http://www.acquerra.com.au/astro/
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alpal
sage
Reged: 06/15/09
Posts: 204
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Thanks Bird,
The whole world is waiting for the results.
This sandwich mirror has the capacity to re-write the
textbooks but your previous results are a hard act to follow.
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Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
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mikey cee
Post Laureate
Reged: 01/18/07
Posts: 3531
Loc: bellevue ne.
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Willy Wonka 
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7x35 and 10x50 sears tower binocs, 3" f/10 edmunds reflector, 2.4" f/11.7 manon refractor, 6" f/8 jaegers refractor, "The 8 Ball" 8" f/13.3 brandt refractor, 3" f/15.8 sans&streiffe refractor, 3.1" f/15 selsi refractor(towa 339), 2.4" f/15 sears refractor, selsi 30x30mm spyglass, criterion 5-draw 25x45x75x spyglass(1957), 4.25" f/14.8 tasco 20te.
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alpal
sage
Reged: 06/15/09
Posts: 204
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What has Willy Wonka got to do with mirrors?
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Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
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Don W
Postmaster
Reged: 05/19/03
Posts: 14628
Loc: Wisconsin, USA
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Yeah, what does it have to do with mirrors?
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Don Wyman
Obsession 18" f/4.5 #1166
W/Argo Navis DSC and Torus Primary
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tim53
Pooh-Bah
Reged: 12/17/04
Posts: 1459
Loc: Highland Park, CA
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Well, I looked through a lot of friends' Enterprise Optics mirrors before I had Ed Beck make my 12.5" f/23 Cassegrain. I can't afford to buy a bunch of mirrors and compare them. I also know Ed reasonably well, and that counted, too.
Cool tidbit: His mirror grinding machine was originally built by Alika Herring when they were at Cave.
-Tim.
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"We`re just waiting looking skyward as the days come down.
Someone promised there`d be answers, if we stayed around."
-Orchestral Maneuvers in the Dark, "The Romance of the Telescope"
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dave b
Post Laureate
Reged: 05/10/05
Posts: 3547
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Quote:
Willy Wonka
The suspense is terrible... I hope it'll last - WW
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dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
|
dave b
Post Laureate
Reged: 05/10/05
Posts: 3547
|
|
here is a 36" sandwich mirror:
http://www.normandfullumtelescope.com/Gallery/displayimage.php?pid=3&fullsize=1
--------------------
dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
|
Lalith
member
Reged: 06/09/06
Posts: 49
Loc: IL
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|
Quote:
that nemesis blank is a sandwich mirror, not honeycomb.
mirrors of that style have been around for a long time, zambuto had made some mirrors like that with blanks that came from a company called stablelite, back in the 90s. hextech was another company that did large sandwich mirrors in that style.
this would be an example of a honeycomb mirror:
http://www.embeddedrf.com/Lookinglass_Webpage_Files/Webbed_Backed/Webbed_Blank.html
Is that web page current. Do they still make those webbed blanks, prices given there looks good.
Lalith
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johnnyha
Pooh-Bah
Reged: 11/12/06
Posts: 1139
|
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Quote:
What has Willy Wonka got to do with mirrors?
Everlasting DobStoppers?
--------------------
Johnny
Spicewood, TX
Sherman Oaks, CA
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alpal
sage
Reged: 06/15/09
Posts: 204
|
|
Quote:
here is a 36" sandwich mirror:
http://www.normandfullumtelescope.com/Gallery/displayimage.php?pid=3&fullsize=1
Wow Dave B,- what a huge mirror.
When will it be installed & where?
--------------------
Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
|
dave b
Post Laureate
Reged: 05/10/05
Posts: 3547
|
|
Quote:
Quote:
that nemesis blank is a sandwich mirror, not honeycomb.
mirrors of that style have been around for a long time, zambuto had made some mirrors like that with blanks that came from a company called stablelite, back in the 90s. hextech was another company that did large sandwich mirrors in that style.
this would be an example of a honeycomb mirror:
http://www.embeddedrf.com/Lookinglass_Webpage_Files/Webbed_Backed/Webbed_Blank.html
Is that web page current. Do they still make those webbed blanks, prices given there looks good.
Lalith
fred has his fingers in many different projects, but if you have the money and can handle the 6 month wait, he will cast you a blank.
--------------------
dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
|
dave b
Post Laureate
Reged: 05/10/05
Posts: 3547
|
|
Quote:
Quote:
here is a 36" sandwich mirror:
http://www.normandfullumtelescope.com/Gallery/displayimage.php?pid=3&fullsize=1
Wow Dave B,- what a huge mirror.
When will it be installed & where?
I heard that one of them went to new york, but I have no idea if it is gathering any starlight as of yet.
--------------------
dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
|
alpal
sage
Reged: 06/15/09
Posts: 204
|
|
Quote:
I heard that one of them went to new york, but I have no idea if it is gathering any starlight as of yet.
I wonder if it is from the Newport Glassworks?
see link http://www.newportglass.com/afuscelr.htm
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kfrederick
professor emeritus
Reged: 02/01/08
Posts: 669
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MARK HARRY MAKES KILLER MIRRORS HE LIKES SMALLER MIRRORS 14INCHES AND DOWN /NOT SURE IF HE IS STILL TAKING ORDERS?
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alpal
sage
Reged: 06/15/09
Posts: 204
|
|
I wonder how they mount those sandwich mirrors?
They look so delicate that if you blew on them
they would break!
--------------------
Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
|
Lalith
member
Reged: 06/09/06
Posts: 49
Loc: IL
|
|
I contacted him, he says he is not taking new orders now as there is a big backlog. I am also wondering how one mount such a mirror. Is there any information available on the internet on mirrors made with those blanks.
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dave b
Post Laureate
Reged: 05/10/05
Posts: 3547
|
|
Quote:
Quote:
I heard that one of them went to new york, but I have no idea if it is gathering any starlight as of yet.
I wonder if it is from the Newport Glassworks?
see link http://www.newportglass.com/afuscelr.htm
no, those 36" blanks are from Canada
--------------------
dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
|
alpal
sage
Reged: 06/15/09
Posts: 204
|
|
Quote:
I contacted him, he says he is not taking new orders now as there is a big backlog. I am also wondering how one mount such a mirror. Is there any information available on the internet on mirrors made with those blanks.
Are you talking about Mark Harry?
I would also like to know how to mount a sandwich mirror.
I can't see how to do it without putting an uneven stress
somewhere on it.
That is why I am so interested in Anthony Wesley's mirror
but I know he'll work out a good way.
He hasn't supplied any photos yet of a mounting technique.
Maybe he'll need a couple of tries to get it right?
--------------------
Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
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alpal
sage
Reged: 06/15/09
Posts: 204
|
|
Quote:
no, those 36" blanks are from Canada
OK - I'll be interested to see if that mirror can be
ground properly & whether it works well.
--------------------
Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
|
Bird
Post Laureate
Reged: 08/07/03
Posts: 3024
Loc: Canberra, Australia
|
|
Quote:
That is why I am so interested in Anthony Wesley's mirror
but I know he'll work out a good way.
He hasn't supplied any photos yet of a mounting technique.
Maybe he'll need a couple of tries to get it right?
Yep, that's about right... when I've got it working I'll let you know...
cheers, Bird
--------------------
Deep Sky Optics 13.1" f/5.5 newtonian,
PGR Dragonfly Express, PGR Dragonfly 2
RedHat Linux + Coriander
http://www.acquerra.com.au/astro/
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dave b
Post Laureate
Reged: 05/10/05
Posts: 3547
|
|
Quote:
Quote:
no, those 36" blanks are from Canada
OK - I'll be interested to see if that mirror can be
ground properly & whether it works well.
4 of these mirrors are already figured and coated, but i have not seen any finished scopes.
--------------------
dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
|
Biff
Carpal Tunnel
Reged: 09/04/05
Posts: 2372
Loc: Courtice, Ontario
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Who in Canada is making those blanks? Is it Normand Fullum?
--------------------
Ryan
Antares 200mm f/6 Dob & 130mm f/5 Travel Dob.
Projects on the go...
- a couple 80mm SS refractors on the back burner.
- a few small mirrors awaiting polishing
- 260mm f/7.15 mirror... still polishing
Member of DRAA
 My house.
 DRAACO
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Lalith
member
Reged: 06/09/06
Posts: 49
Loc: IL
|
|
Quote:
Quote:
I contacted him, he says he is not taking new orders now as there is a big backlog. I am also wondering how one mount such a mirror. Is there any information available on the internet on mirrors made with those blanks.
Are you talking about Mark Harry?
One replied my email was Fred.
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mark cowan
Vendor (Obsidian Optics)
Reged: 06/03/05
Posts: 2159
Loc: salem, OR
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Quote:
Who in Canada is making those blanks? Is it Normand Fullum?
I believe it is Jean-Guy Moreau but I've never verified it. They look very much like what he's been making.
Best,
Mark
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dave b
Post Laureate
Reged: 05/10/05
Posts: 3547
|
|
Quote:
Quote:
Who in Canada is making those blanks? Is it Normand Fullum?
I believe it is Jean-Guy Moreau but I've never verified it. They look very much like what he's been making.
Best,
Mark
you are right mark
--------------------
dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
|
BluewaterObserva
Post Laureate
Reged: 05/18/04
Posts: 4968
Loc: Zuni Mtns, NM
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I have to admit, those mirrors, just from the look of them scare me!!!
I think I will stick to thin, solid mirrors.
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alpal
sage
Reged: 06/15/09
Posts: 204
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Quote:
I have to admit, those mirrors, just from the look of them scare me!!!
I think I will stick to thin, solid mirrors.
I think the conical section mirrors are easier to mount.
My next mirror will be conical.
--------------------
Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
|
PrestonE
Pooh-Bah
Reged: 04/29/05
Posts: 1170
Loc: Houston,Texas
|
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Jean-Guy's blanks have improved greatly I believe.
Our 14.5" only had a problem because he tried to laminate 2 thin plates together for the face plate that had a few small areas the did not bond and were thus air pockets...
Using Carl Zambuto's method of fast polish to a sphere and then figuring...these air pockets under the heat of the polish to a sphere caused these areas to rise or expand and thus when one tested the optic they ended up low as we polished off the expanded areas...
He is now using a single plate on top and I believe that should resolve the issues...
We never saw any problem with print through, thou we had about a balance on the overarm such that there was less than 0.5 oz pressure per in sq on the surface...
Hope this sheads some light... 
Very Best Regards,
Preston
--------------------
A few I enjoy,
and a few more in the works ;<)
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GlennLeDrew
Pooh-Bah
Reged: 06/18/08
Posts: 1298
Loc: Ottawa, Ontario, Canada
|
|
To answer an earlier comment on the supposed "disappearance" of Peter Ceravolo from the amateur scene... He's offering high-end corrected Cassegrains, designed primarily for imaging. Vist the Ceravolo website to see what's up...
--------------------
Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Home-made Mk II RA bino, using interchangeable objectives and eyepieces
My Gallery
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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alpal
sage
Reged: 06/15/09
Posts: 204
|
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Surely this thread should include mirrors that are refigured
by experts?
( Coulter mirrors had a bad name.)
For instance I read that many people refigured
17.5" Coulter mirrors into excellent mirrors.
Maybe the best mirrors are ones that experts spent a lot of
time refiguring & recoating?
Think about it - if someone had endless time & a proper
way of testing a mirror surely they would make a mirror
more accurate than any mass produced mirror?
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mark cowan
Vendor (Obsidian Optics)
Reged: 06/03/05
Posts: 2159
Loc: salem, OR
|
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Quote:
Think about it - if someone had endless time & a proper
way of testing a mirror surely they would make a mirror
more accurate than any mass produced mirror?
Indeed.
Some years back I was part of a group wandering around in the dark at the Oregon Star Party, and one of the people asked the question, "Who makes the best mirrors?" We proceeded to name various people, and commercial firms, but his answer was "Amateurs! Amateurs make the best mirrors."
If you have endless time and a proper way of testing you can indeed make a mirror more accurate than any "mass" produced mirror. My favorite mirror is an 8" f/5.8 that's 15 years old and has never been beaten, rarely even equaled. But it took forever to finish it, involving, at one point, going back to a sphere to start over even though it was good enough to show the polar caps of Mars uncoated.
It showed me what a perfect mirror could do though, and chasing that goal commercially - essentially, how to produce perfect mirrors every time out? - involves complications well beyond what anybody would ever want to go through, just to make their own highly accurate mirror for their own use.
Best,
Mark
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alpal
sage
Reged: 06/15/09
Posts: 204
|
|
Quote:
( Coulter mirrors had a bad name.)
For instance I read that many people refigured
17.5" Coulter mirrors into excellent mirrors.
Oh dear - it seems I made a mistake.
An expert told me today that Coulter mirrors were made out
of cheap soda glass & were never excellent even when re-figured.
Apparently they were only good for deep sky viewing but
couldn't hold high magnification on planets.
--------------------
Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
|
alpal
sage
Reged: 06/15/09
Posts: 204
|
|
Quote:
My favorite mirror is an 8" f/5.8 that's 15 years old and has never been beaten, rarely even equaled.
Hi Mark - is that mirror for sale?
One day I might want it.
I have yet to fully test my telescope as it wasn't fully aligned before.
--------------------
Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
|
dave b
Post Laureate
Reged: 05/10/05
Posts: 3547
|
|
Quote:
Quote:
( Coulter mirrors had a bad name.)
For instance I read that many people refigured
17.5" Coulter mirrors into excellent mirrors.
Oh dear - it seems I made a mistake.
An expert told me today that Coulter mirrors were made out
of cheap soda glass & were never excellent even when re-figured.
Apparently they were only good for deep sky viewing but
couldn't hold high magnification on planets.
don't believe any so-called experts.
the coulters were indeed made of Pyrex.
they just had horrible figures. little by little, all those old coulter mirrors are being refigured into real mirrors. in the hands of a skilled optician they come out as good as any other glass.
BTW even if they were made of soda lime glass, a skilled optician can make just as good of a mirror as pyrex would.
--------------------
dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
|
alpal
sage
Reged: 06/15/09
Posts: 204
|
|
Quote:
don't believe any so-called experts.
Fair enough - actually I will be checking out Jupiter using a dobsonian
with a large refigured Coulter mirror within one week.
I'll be able to see for myself & form my own opinion.
I'll let everyone know.
--------------------
Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
|
Gord
professor emeritus
Reged: 01/06/04
Posts: 694
Loc: Toronto, ON, Canada
|
|
Hi,
Normand Fullum has been mentioned a few times in the thread already, but I will put his name forward again. I have 2 of his mirrors, and have looked through a number of others. All have been incredible, and all people I have talked with that have them are incredibly pleased.
I know he puts a great deal of care into his work, and this is also very evident in the wood-working he does for his scopes. Good mirrors require effort and attention to details (so I keep hearing) and this is one individual who excels at this.
Clear skies,
-Gord
--------------------
* Celestron C10/Normand Fullum primary
* Tasco 11TR/Normand Fullum primary
* Orion StarBlast
* Orion Apex 102
* SkyWatcher 80ED
* Celestron CG5a mount
* MallinCam Pro & Color II
* Lots of other astro toys
...and the best wife I could ever dream of for letting it all happen!
--------------------
|
Wes James
Post Laureate
Reged: 04/12/06
Posts: 3460
|
|
After seeing Dick Parker's double pass autocollimator test bench in use, and understand the testing method- if I were looking for a premium mirror, one of the questions I would ask is "How was it tested?" Autocollimation tells you in one glance what it takes many calculations in zonal testing- each reading subject to interpretation- to do. Ross null testing also tells you in one glance what you need to know.
--------------------
Wes
Atlantic Beach, FL
Some bino’s from Miyauchi 5x32 Binon's up through Garrett 20x110 Signature's,
Some telescopes from a Stellarvue 80mm NHNG up through a couple of 8” reflectors…
And a wonderful 4.25" Delmarva Shiefspiegler!
Some good friends, made here on C/N.
Oh- several cats and a wonderful wife!
Anyone want a cat???? :-O
"When your work speaks for itself- Don't Interrupt" -Gamble Rogers
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mark cowan
Vendor (Obsidian Optics)
Reged: 06/03/05
Posts: 2159
Loc: salem, OR
|
|
Quote:
Hi Mark - is that mirror for sale?
One day I might want it.
I have yet to fully test my telescope as it wasn't fully aligned before.
Never. 
And I only go down to 10" (well, ok, 9.8") now.
Best,
Mark
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alpal
sage
Reged: 06/15/09
Posts: 204
|
|
Quote:
Normand Fullum has been mentioned a few times in the thread already, but I will put his name forward again. I have 2 of his mirrors, and have looked through a number of others. All have been incredible, and all people I have talked with that have them are incredibly pleased.
Thanks Gord,
I just went to his website & it's interesting.
Check out the "sandwich" mirrors at the bottom of the photo.
See this link for his mirror prices:
http://www.normandfullumtelescope.com/mirror_en.html
--------------------
Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
|
Jim Romanski
scholastic sledgehammer
Reged: 01/02/05
Posts: 844
Loc: Guilford, Connecticut
|
|
Quote:
don't believe any so-called experts.
the coulters were indeed made of Pyrex.
they just had horrible figures.
I wouldn't state this as an absolute. There are good ones out there. I have two coulter mirrors that I never had tested but give very nice images. I'm sure they could be improved upon but they are good enough in my opinion that I don't plan to re-figure them for quite a while.
--------------------
Jim
17.5" Dob "Project"
13.1" Coulter
8” Cave
NP 101 on a CG-5
25x100 binos
Naglers, Ethos, etc.
|
dave b
Post Laureate
Reged: 05/10/05
Posts: 3547
|
|
some of the thicker blank, longer focal length mirrors i have seen tested at 1/4 wave, but ive never seen a good coulter 17" ever (unless it had been refigured)
i really want to see one of the coulter 29" mirrors on the bench....
--------------------
dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
|
Jim Romanski
scholastic sledgehammer
Reged: 01/02/05
Posts: 844
Loc: Guilford, Connecticut
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|
Well, for what it's worth, last weekend I observed next to a friend with a 16" Lightbridge and I'd say that my 17.5" was at least as good.
One of my best views of Jupiter was with the 17.5" (while the NP101 looked on).
That said, I've seen some real stinkers too.
--------------------
Jim
17.5" Dob "Project"
13.1" Coulter
8” Cave
NP 101 on a CG-5
25x100 binos
Naglers, Ethos, etc.
|
Ian Robinson
Pooh-Bah
Reged: 01/29/09
Posts: 1165
Loc: Gateshead.NSW Nth Coast,Austra...
|
|
Quote:
here is a 36" sandwich mirror:
http://www.normandfullumtelescope.com/Gallery/displayimage.php?pid=3&fullsize=1
That thing weights 376 pounds .... he's a strong lad or a brave one to be lifting it like that.
I bet he put it back on the bench quick smart after the picture was taken.
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Ian Robinson
Pooh-Bah
Reged: 01/29/09
Posts: 1165
Loc: Gateshead.NSW Nth Coast,Austra...
|
|
Quote:
That 16" f/4 mirror has been in the works since January... it took a *long time* for Newport to cast it and get it to me, I received the blank in mid August.
The delivery date for the finished mirror is not yet known, maybe in the next month or so with any luck... as soon as I know how it performs I'll post more info.
The mirror is designed for fast cooling, not only the radial fins and open design but also the array of holes in the back surface where I can blow air in between the front and back.
cheers, Bird
If you don't mind telling us , or PMing the answer , how much did the sandwich 16" FS blank cost you and how much will it cost to have it figured and polished ?
Do you apply the same flotation as a solid mirror to these ?
|
llanitedave
Humble Megalomaniac
Reged: 09/26/05
Posts: 12942
Loc: Amargosa Valley, NV, USA
|
|
Quote:
Quote:
don't believe any so-called experts.
the coulters were indeed made of Pyrex.
they just had horrible figures.
I wouldn't state this as an absolute. There are good ones out there. I have two coulter mirrors that I never had tested but give very nice images. I'm sure they could be improved upon but they are good enough in my opinion that I don't plan to re-figure them for quite a while.
I had a 10" full thickness Coulter that I bought in 1977 that was an excellent performer. It gave essentially perfect images in focus, although at the time I didn't know enough about star testing to give it the in and out of focus tests.
Unfortunately, I stupidly scratched it up when I was trying to remove the old coating myself, and replaced it in the 1990's with one of their thinner mirrors. It's figure was fair at best, and the roughness was visible in good seeing.
My plan is to send the newer one out to have it refigured (in a year or two), and keep the original as an experimental blank, so that someday I can say I actually did produce my own mirror.
--------------------
"Since the process of science generates more mysteries than it solves, I predict that we'll never learn everything: and we'll continue to generate new ignorance at the speed of knowledge."
"S.O.E." (Sauron's Other Eye), with 16" Royce conical mirror: A permanent work in progress.
10" Homebuilt dob, old Coulter mirror
Under Construction: The "Eye of Sauron" Observatory!
|
pstarr
Pooh-Bah
Reged: 09/17/04
Posts: 1280
Loc: NE Ohio
|
|
I had one of the early Coulter f-5.6 10" mirrors I bought new. Before I finished the scope, I took it to a local ATM who made mirrors to have it tested. He didn't do any zonal measurements but said it was very smooth and free from any zones, with a good edge. The mirror was an excellent performer.
--------------------
Paul
10" Home built F-6 Eq Newt. w/Zambuto mirror, built for lunar and planetary viewing.
12'x12' roll-off roof observatory
6" Home built f-6 Newt. w/Dick Wessling mirror on CG-5 Eq. mount, built for high resolution work.
4.5" Orion Starblast on Eq. mount
TV Radians 4,5,6,8,10,12,
Pentax XL 10.5mm
Pentax XW 14mm
Baader Hyperion 17mm
4&5mm UO Abbe Orthos.
3.2mm TMB planetary
TV 2.5x barlow, TV 1.8x barlow
My equipment philosophy... If it ain't broke, fix it anyway.
|
auriga
scholastic sledgehammer
Reged: 03/02/06
Posts: 795
|
|
Quote:
I think Dick Wessling deserves a mention here. He is right up there with those who were mentioned so far. Dick's web site.
I agree with this. I own 3 Wessling mirrors and all three are superb.
Bill Meyers
|
alpal
sage
Reged: 06/15/09
Posts: 204
|
|
Pity Dick Wessling doesn't give the pricing of his mirrors & the
optical specifications on the website.
--------------------
Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
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pstarr
Pooh-Bah
Reged: 09/17/04
Posts: 1280
Loc: NE Ohio
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Quote:
Pity Dick Wessling doesn't give the pricing of his mirrors & the
optical specifications on the website.
He may not give the info on the web site but if you contact him, you will find a very nice and helpful person. His target accuracy is 1/40th wave and his prices are reasonable IMO. He will answer any email inquiries you may have. Here is the final results on a 6" he figured for me.
--------------------
Paul
10" Home built F-6 Eq Newt. w/Zambuto mirror, built for lunar and planetary viewing.
12'x12' roll-off roof observatory
6" Home built f-6 Newt. w/Dick Wessling mirror on CG-5 Eq. mount, built for high resolution work.
4.5" Orion Starblast on Eq. mount
TV Radians 4,5,6,8,10,12,
Pentax XL 10.5mm
Pentax XW 14mm
Baader Hyperion 17mm
4&5mm UO Abbe Orthos.
3.2mm TMB planetary
TV 2.5x barlow, TV 1.8x barlow
My equipment philosophy... If it ain't broke, fix it anyway.
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PrestonE
Pooh-Bah
Reged: 04/29/05
Posts: 1170
Loc: Houston,Texas
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Hi Ian, try closer to 100 pounds...look at the front and back plates...calculate their weight and that is most of the weight...
The bars that space the plates likely do not weigh 10 pounds total...
JMHO
Best Regards,
Preston
--------------------
A few I enjoy,
and a few more in the works ;<)
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alpal
sage
Reged: 06/15/09
Posts: 204
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Quote:
He may not give the info on the web site but if you contact him, you will find a very nice and helpful person. His target accuracy is 1/40th wave and his prices are reasonable IMO. He will answer any email inquiries you may have. Here is the final results on a 6" he figured for me.
Those results on the graph are so good that they seem
almost impossible. It's much better than 1/100th wave PV!
Who did the graph?
--------------------
Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
|
pstarr
Pooh-Bah
Reged: 09/17/04
Posts: 1280
Loc: NE Ohio
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The graph is the test results from Dick Wessling. Numbers are just that. I don't put a whole lot of faith in them. What I can say for sure is that the mirror star tests and performs very similar to the 10" Zambuto mirror I have. To my eye, they both have almost text book diffraction patterns. It is really not surprising that a high degree of accuracy could be reached on a small mirror like a 6", especially by someone highly skilled who wants to spend the time on it. Dick had just completed a 16" f-4 before doing my 6". He commented on how easy the 6" was to figure by comparison. It gives excellent planetary, lunar and double star images. I'm very happy with it.
--------------------
Paul
10" Home built F-6 Eq Newt. w/Zambuto mirror, built for lunar and planetary viewing.
12'x12' roll-off roof observatory
6" Home built f-6 Newt. w/Dick Wessling mirror on CG-5 Eq. mount, built for high resolution work.
4.5" Orion Starblast on Eq. mount
TV Radians 4,5,6,8,10,12,
Pentax XL 10.5mm
Pentax XW 14mm
Baader Hyperion 17mm
4&5mm UO Abbe Orthos.
3.2mm TMB planetary
TV 2.5x barlow, TV 1.8x barlow
My equipment philosophy... If it ain't broke, fix it anyway.
|
alpal
sage
Reged: 06/15/09
Posts: 204
|
|
Quote:
It gives excellent planetary, lunar and double star images. I'm very happy with it.
That's the most important thing.
I am just waiting on good weather to test my Newtonian
after it has been aligned & I've made new tube rings for it.
I am supposed to have a top grade mirror so it will be interesting.
--------------------
Location: Melbourne Australia.
8" f6 custom built Newtonian with
EQ6 Pro mount.
Takahashi LE 5mm eyepiece & 2 x Tak. Barlow.
Williams Optics Eyepieces - 2" 40mm & 25mm, 1.25" 15mm & 9mm.
Saxon 11 x 70 binos.
Set of 11 Hirsh Optics 1.25" filters.
Set of 4 Orion 2" filters.
Antares 1.25" ALP filter.
+ One cheap 4.5" Newt. complete with eyepieces.
|
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