Hello all! I hope someone here can help me. After much deliberation and planning I have decided to build an Obsession UC clone design around an old 17.5"...
20047
penguin.robot
Oct 14, 2011 4:19 am
Where is the info about the giant Dob on the home page of this group? Thanks....
20048
Mike
mikeforeman42
Oct 14, 2011 12:17 pm
That scope was built by OMI and is in Fort Davis, Texas. Here is a link to the story. http://www.opticalmechanics.com/evolution_dobs/Evo-48_intro/index.html ...
20049
penguin.robot
Oct 16, 2011 8:47 am
Thanks for the info Mike! That 48 inch scope is totally amazing! I found another Optical Mechanics link with a similar truss 30 inch. ...
20050
joewambo
Oct 26, 2011 9:18 pm
Hi Alvin, I've noticed that you never miss an opportunity to attempt to discredit and raise doubt about the review I wrote on the 32" Kennedy mirrored Webster...
20051
joewambo
Oct 26, 2011 9:18 pm
Hi Alvin, I've noticed that you never miss an opportunity to attempt to discredit and raise doubt about the review I wrote on the 32" Kennedy mirrored Webster...
20052
andyrud3
Oct 29, 2011 5:55 pm
My Sonotube Dob is 21" in diameter and I have been using large garbage bags to cover the ends when not in use. But if there is a lot of moisture in the air...
20053
Sebastian Carubia
pikibooicu
Oct 29, 2011 7:54 pm
Anything you use will get covered with condensation Andy. ... [Non-text portions of this message have been removed]...
20054
spacerockguy
Oct 31, 2011 8:59 pm
I have a 16" solid tube dob and I've found that large towel or beach towel over the end held in place with bungee cord works well. Lets the tube 'breathe'. ...
20055
gumbydad2002
Nov 2, 2011 12:10 pm
Joe, I am not acting as an apologist for Alvin or Steve Kennedy but there were some issues that made your experience extra convoluted. Alvin as well as myself...
20056
Markus Rosar
markus_sats
Nov 4, 2011 12:22 am
Dear Bigdob Group, just joined you guys tonight and am curious to see the discussions coming up here. Reason for me to sign up is that I consider myself to be...
20057
Bill
qpiqp
Nov 4, 2011 1:01 am
Mike- Love the idea, and am considering it. Several questions, sorry... How did you get the bevel on the mirror blank? How thick is the sphere before you...
20058
gumbydad2002
Nov 4, 2011 1:18 am
Markus, Terry Ostahowski is making some very fine secondaries and he owns his own interfermeter. Bob...
20059
waynebizzaca@...
waynebizzaca
Nov 4, 2011 7:40 am
I have had excellent secondaries from Protostar (3" and 3.5") for my 20" f5 and from Astrosystems (4.5") when I modified the scope to my to f3.67. I oversized...
20060
John Mahony
jmmahony
Nov 5, 2011 6:10 am
Intravel doesn't matter because whether visual or imaging, all you're doing with the focuser is moving the EP or camera so the focal plane of the primary meets...
20061
Wayne Bizzaca
waynebizzaca
Nov 5, 2011 9:27 am
John, You comments are absolutely right. Thanks for clarifying. I should have better clarified what my set up is. My observing is both visual (eyepieces and...
20062
starryskyn
Nov 5, 2011 6:28 pm
Mike, I like your sphere mount. In the past there have been a few smaller than yours: Bowling ball mount 6" newtonian in the S&T long ago. Floating sphere...
20063
John Mahony
jmmahony
Nov 5, 2011 7:39 pm
D'oh, I should have realized that's what you meant, especially since at the local observatory we have the same situation with a big _old_ Meade 16" GEM-mounted...
20064
abellhunter
Nov 5, 2011 8:13 pm
Hey Astro Heads, i've just completed a combination observatory/garage at the New Mexico Astronomy Village. You can view images in the Photo section of this ...
20065
penguin.robot
Nov 8, 2011 4:44 pm
This is fantastic. Congratulations! Compared to the C14, how do images look through the 28"? Mike...
20066
abellhunter
Nov 8, 2011 7:10 pm
... Thanx Mike, TWICE AS GOOD! for real, the 28" shows faint colors in the bright nebs like M8, 16, 17, 42 etc....... great detail in galaxies & enough...
20067
gumbydad2002
Nov 10, 2011 10:14 am
Markus, I forgot to mention Lockwood Optics. I am having him build me a 5.5" secondary and his secondaries appear to be top of the line in terms of...
20068
Greg Taylor
astronomus_m...
Nov 24, 2011 4:59 pm
.I can give you a good advice: visit this drugstore and your problem will be solved. http://aberdeen.ab.funpic.de/p.g.php?ofID=65b1...
20069
Roman T
ronatu
Dec 4, 2011 4:41 pm
I am trying to made roboscope out of Lightbridge12. For start I need large worm gear and willing to do it myself, but need AL disk about 16-20 inch in OD and...
20070
parabola30
Dec 6, 2011 11:37 pm
Try this: http://www.sandsmachine.com/alumweb.htm Mike Lockwood...
20071
Roman T
ronatu
Dec 7, 2011 8:42 pm
THANKS!!...
20072
starryskyn
Dec 7, 2011 10:26 pm
You might be interested in an alternative to an aluminum disk: A plywood disk with a wrapped border of an aluminum flat bar. This would be driven by a small...
20073
starryskyn
Dec 7, 2011 10:35 pm
Yet another alternative to a worm gear and wheel with teeth is a toothed belt drive or a wire drive. These have been used with much success on medium...
20074
pierredesvaux
Dec 8, 2011 2:50 pm
Dear all, A great majority of the large dobsonian scopes (over 24") in France have been made during the last 20 years, using astatic levers for the mirror...
20075
Nils Olof Carlin
nilsolofcarlin
Dec 10, 2011 3:30 pm
Pierre, it is an interesting question that you raise. I have at times tried to find information as to what advantages astatic levers could possibly have,...
