Kevin,
For the past year or so, Mag1 has been shipping all Portaballs with a
curved-vane spider. I have one of these that is not quite a year old.
Yes, it eliminates the diffraction spikes. But remember, it doesn't
change the fact that the spider still obstructs, scatters, and refracts
light -- so the light that is scattered just goes elsewhere, not into
straight diffraction spikes. As far as I can tell, this is a
preference issue: whether you object to diffraction spikes or not.
But I don't think that the curved-vane spider will make the image
better in any other respect.
Bob
--- grimly_fiendish@comcast.net wrote:
> Recently I have begun building a 16" truss tube telescope and I have
> asked and received help from several people on this list with
> materials and parts. I have gotten to the point where I have to
> decide on a spider and I was first considering purchasing a Protostar
> as they come highly recommended by several people, but recently I
> came across the curved vane spider and was wondering if anyone has
> used one and if the claims are true. I would appreciate any advice,
> please reply to me off list.
>
> Clear skies,
>
> Kevin
__________________________________
Do you Yahoo!?
Win a $20,000 Career Makeover at Yahoo! HotJobs
http://hotjobs.sweepstakes.yahoo.com/careermakeover
Received on Fri Apr 30 10:25:53 2004