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Posts Made By: David Tarshis

May 24, 2004 02:15 PM Forum: Astro-Physics

Custom mount

Posted By David Tarshis

Everyone should have a mount like this for their AP's.

May 25, 2004 09:00 PM Forum: Deep Sky Observing

Mexico next month

Posted By David Tarshis

I will be in Puerto Vallarta next month. Besides Omega Centari, what other objects will be worth taking my ED80 with me. Thanks

May 26, 2004 09:37 AM Forum: Telescope Making

Triangles for mirror cell, help

Posted By David Tarshis

Can someone tell me how to translate this diagram so I can lay out a template to cut the steel for the triangles? What is a vertex? Thanks
This is for a 12.5 btw

June 1, 2004 07:27 AM Forum: Telescope Making

Secondary questions for 12.5 f6.4

Posted By David Tarshis

I live in Portland OR. How important would it be to have a dew heater for my secondary? I haven't had a problem with dew on my sct, but I haven't pulled that out since I got my ED80 either. I'm thinking about getting the Protostar for my 12.5 and was wondering if it was worth getting the heater for it. Adhesive vs shroud mounting, pro's con's, and straight vane vs curved, worth the difference in price? Thanks

June 5, 2004 08:50 AM Forum: Telescope Making

Alum vs Stainless mirror cell triangles

Posted By David Tarshis

Making the triangles for my mirror cell for a full thickness 12.5 f/6.4. I'm looking for pro's con's for alum vs ss. Thanks

June 6, 2004 04:26 PM Forum: Telescope Making

1/8 or 1/16 wall thickness for cell? 12.5 f/6.4

Posted By David Tarshis

I'm trying to save some weight. Can I get away with 1/16 wall thickness for the rungs? Thanks

June 9, 2004 09:36 AM Forum: Telescope Making

Secondary size for 12.5 f/6.4

Posted By David Tarshis

I would just like some confirmation. Using Newt 2.5, I came up with 1.52 secondary with a 14" secondary cage id. At first I thought I was going with a 2.14. Would a 1.83 work? It says I will have vignetting at focuser of 75% ray. Not sure what that means. Thanks

June 12, 2004 03:35 PM Forum: Telescope Making

Secondary mirror

Posted By David Tarshis

My primary will be a 12.5 f/6.4 Swayze mirror. Pro's con's for quartz vs Pyrex. Besides the money. Thanks

July 4, 2004 10:07 AM Forum: Telescope Making

Secondary cage id 12.5 f6.4

Posted By David Tarshis

According to "the book", the id of my secondary cage should be 13.1 inches. How critical is this measurement? Thanks

July 12, 2004 01:02 PM Forum: Equipment Talk

Best Laser collimation tool recomendations

Posted By David Tarshis

Or best method if laser is not the best for my 12.5 newt. Thanks