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Posts Made By: John Dennis

November 27, 2002 04:51 PM Forum: Astro Binoculars

Binocular Repair

Posted By John Dennis

Hello,
I hope this is the site to use for my question.
Where might I get a pair of ? WW II ? vintage 7x50's
Freshened -up ? They have a scikle and star logo and
some kind of pump near the hinge. They have individual
eye focusers and these are not tight. I often use them,
but would use them more if this problem could be corrected.
My first views of Jupiter with his 4 moons were with these!
Thank you in advance,
John Dennis

March 3, 2004 07:07 PM Forum: Telescope Making

Truss poles -Insulation?

Posted By John Dennis

Hello to all,
These may seem weird questions, but they are honest ones.

What material is better( the plastic-like or the rubber-like pipe insulation) to cover truss poles?

Do you glue them on or just use the self sticking edges?

What is the reason insulation is used at all ?

Thanks in advance, John


March 6, 2004 08:25 AM Forum: Deep Sky Observing

Jay McNeil on NPR

Posted By John Dennis

Scott Simon interviewed Mr McNeil today on Weekend Edition.
The audio is not availiable yet. 1130 EST. www.NPR.COM
Exciting times we live in !

March 14, 2004 06:31 PM Forum: Equipment Talk

aperture mask

Posted By John Dennis

I was reading a thread from the archives from November 2003 about the use of these masks.
My question concerns the placement of it. Most of the comments led me to believe that one must place it on the focuser end, but can it be integrated into the mirror box cover of a truss dob ? Would you need to cut elipses or circles? (18 inch f/5)
Any comments will be appreciated, thank you.
John

September 6, 2004 04:05 PM Forum: Star Parties

Great Lakes Star Gaze

Posted By John Dennis

Sept 17-19, My wife and I are planning to attend.
Hope for clear skies !
Any good info about this gathering ?
Is it better to camp in the field or the campground?
Good places to eat , local history. Will we be off the Presidential campaign trail?
Thanks in advance, John

June 3, 2005 07:17 AM Forum: Telescope Making

reverse crayford

Posted By John Dennis

Hello All,
I am starting the decision tree for building a 12 inch
f/5 truss dob with a 2.6 inch secondary . What are the pros and cons for the use of a reverse vs. standard
focuser ?
Thanks in advance.
John

July 2, 2005 08:47 AM Forum: After Dark

First Light Ideas

Posted By John Dennis

Hello, Folks,

I have never been to a "first light" party.
What are some nice things we might do for
a first time ATM'er to congratulate him and
celebrate a new scope brought into the world ?
Thank you,
John

October 1, 2005 10:26 AM Forum: After Dark

Family

Posted By John Dennis

Hi folks,
I just wish to share a gift I received Friday, Sept 30.
My 27yo daughter asked to come out with me on an observing session! What a thrill.
The sky was darkening by 1930 and the Milky Way was from horizon to horizon by 2000.
We oriented ourselves with some constellations. She knew UMa , Sag, Cas. I added Sco,Cyg,Her,Cap,Peg.
We started with Polaris as a wonderful double star.
Next was M22 + GC discussion followed by M13 and M92
M17 + Nebula discussion with and without OIII
Blinking Planetary and M57-she could see blue-

In M24 is a cool cluster NGC 6603 as well as
several Bernard Dark Nebula and a view of the
Norma spiral arm .(I hope I got that right.)
We went extragalactic and eyeballed M31 then went to the low power scope view. M81,82,51,33-and it's Hydrogen cloud.
We located Venus, Mars, Uranus, and Neptune.
She asked Questions. How do we know how far those ______
are? Parallax, Cepheids, Redshift.
How are galaxies, stars, planets formed?
-Thank Heaven for all the astronomers and writers and folks like you that have pondered, then pounded these
concepts into my head over the years. It was 3 hours
I hope to never forget.
John

May 7, 2006 06:15 AM Forum: Telescope Making

Focuser vs Spider

Posted By John Dennis

Does the focuser position "need" to exactly split the angle between any two arms of the spider? I am using a 4 vane spider. Instead of placing the focuser at the halfway point (45deg), I want to place it at 30 deg. Will this cause any light path problems ?
Thank you, John

February 19, 2012 04:33 PM Forum: Telescope Making

BVC mirror from Canada

Posted By John Dennis

Good evening, I am the second owner of an 18 inch BVC mirror that was manufactured (2003?) by a company in Canada-- AMSPROD. Does someone know of this company or the optician that may have made it? The mirror has been an excellent performer these last eight years. I'm getting a quote from Majestic in NJ for re-coating. Do they do good work? Other suggestions will be helpful ! Thank you in advance. John