Image of the day

Captured by
RICHARD COFER

VdB 141 Ghost Nebula

About Astromart

My Account

New to Astromart?

Register an account...

Need Help?

Posts Made By: Brad Cottingham

April 11, 2002 08:48 PM Forum: Star Parties

Okie-Tex Star Party

Posted By Brad Cottingham
I want to mention the Okie-Tex Star Party this fall. I've been to the last two and had a great time.
http://www.okie-tex.com

Rummored to be there this year:

John Hall - Pegasus Optics
Carl Zambuto - Zambuto Optics
Rick Singmaster - Starmaster Telescopes

Brad

April 22, 2002 04:56 AM Forum: Telescope Making

Mirror Quality

Posted By Brad Cottingham
I'm planning on a travelscope to use when traveling in a motorhome. I'd agreed to purchase a premimum 8" OTA with a 1/20 wave mirror, but the seller backed out at the last moment. (I don't blame him, I'd kept it too if the specs were that good.)

But, that made me start thinking about how high of quality mirror system I might need for a travel system. Say I'm planning on a 8" primary and I rarely expect to use more than 160 power (usually much lower). That's 20x diameter at the max. The top rated mirrors are rated at 50x. So, maybe I really don't need (I'm not saying I might not want) a 1/20th wave mirror for my use.

However, for my use, a smooth mirror finish might be more important than absolute mirror accuracy. I understand a smooth mirror finish produces a higher contrast image.

Could I get your comments on this?

Brad

April 30, 2002 07:07 PM Forum: Off Topic Discussions

Astromart Ads Archive

Posted By Brad Cottingham
I can't find a deleted ad under the archives. I would think you'd be able to recall a deleted ad.

(I'm getting old and can't remember how much I agreed to pay for something :-)

May 3, 2002 12:28 AM Forum: Off Topic Discussions

Johnny Carson

Posted By Brad Cottingham
Since this is the off topic group, I have a question. What's happen to Johnny Carson, and is he still active as an astronomy buff?

Saw him in person years ago when visiting Calif. But when he left the air - he left the air! Just thought of him today when looking through some astro stuff on the internet.

May 7, 2002 05:20 AM Forum: Off Topic Discussions

IBM ThinkPad Power Adapters Needed

Posted By Brad Cottingham
Worried that my employeers expensive Dell notebook might walk at a star party, I picked up a couple of surplus IBM notebooks. Need the 16 volt coaxel and the 20 volt 4 pin unit. Anyone have some surplus units or know where to find them cheap?

Is there an equivlant of Astromart for computers/parts?

Brad

May 18, 2002 06:22 AM Forum: Telescope Making

8" f/5 Ideas

Posted By Brad Cottingham
I'm collecting parts for an 8" f/5 travel scope. Although a 1.25 focuser would probably be adequate, I do have a couple of 2" ep's, so I'll probably build or buy a light weight 2" unit. (Any thoughts on this would be appreciated.)

One unique idea I have is to try to pivot the axis of the dob style mounting near the eyepiece in order to allow a comfortable sitting viewing position no matter whether viewing near the horizion or straight up.

This would require an odd looking balance system hanging out in front of the scope. I've never seen anything like this but I believe it would be possible. As long as it could be detached for transportation.

Has anyone done this?

Brad

May 20, 2002 03:17 PM Forum: Equipment Talk

APM Scopes at NEAF?

Posted By Brad Cottingham
I thought I'd read that the new APM Dobs were suppose to be at NEAF. Did they make it?

Anyone get to inspect one? What were your impressions?

Brad

June 11, 2002 09:19 PM Forum: Telescope Making

Chip in Side of Mirror

Posted By Brad Cottingham
I recently bought a mirror that has a chipped area on the side. I don't think it's anything to worry about, but thought I'd get your input. As you can see, the chipped area just touches the coated area.

Brad

June 21, 2002 05:02 AM Forum: Telescope Making

Foucault Software

Posted By Brad Cottingham
Would appreciate recommendations on software to evaluate foucault data. I'm new at this, and want something relatively simple. Looked at Sixtest, but looks like I'd have to convert all my data to metric.

June 25, 2002 07:36 PM Forum: Telescope Making

Foucault Tester

Posted By Brad Cottingham
Anyone got a good Foucault Tester they want to get rid of, or want to suggest a good design for a build it yourself project? I've searched the web and see all kinds of designs, but I'm one of these guys that almost needs to hold one in his hands and look at one before building.

Brad

Funding Member

Sponsors


View all sponsors

Search