From: Mark Gaffney <markgaffney@me.com>

Date: January 19, 2010 12:03:58 AM MST

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] Spider vanes..

Hi Milton, 

I looked at those links you sent Alberto. I found this image of Alpha Centauri taken with the GSO 8" RC showing the diffraction spikes.

http://www.cloudynights.com/ubbthreads/attachments/2995822-alpahcen.JPG

 I gather it`s not as prominent for stars of less magnitude & that the HST is basically a RC. These curved vanes available in the second of your links will remove the spikes it seems upon a cursory read of the Gary Seronik site. Though I don`t find the spikes as offensive as you do it seems you`ve already found a solution..!  

Mark.

On 19/01/2010, at 4:07 PM, Milton Aupperle wrote:

Mark;

Already did in the last e-mail message on "Virtual Moon Atlas"

http://tech.groups.yahoo.com/group/spiderless/

And try searching with Google / Yahoo etc. with the phrase

curved vanes for telescopes

I found a tonne of links.. like

http://www.garyseronik.com/?q=node/62

http://www.1800destiny.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=1D&Category_Code=CVS

TTYL..

Milton Aupperle

On 18-Jan-10, at 9:31 PM, Mark Gaffney wrote:

Hi Milton,

I`m interested in these problems you`re speaking of because of the  

spider vanes on say the GSO 8" Ritchey Chretien I expessed an interest  

in recently. Would you be able to direct me to any sites you`ve found  

& perhaps Bookmarked that speak about this? Of course say an 8" Edge  

HD scope, wouldn`t be entirely out of my speculations for the future..!

Mark.