Back to Home

ATM Forum Message

Forums: Atm · Astrophotography · Blackholes · Blackholes2 · CCD · Celestron · Domes · Education
Eyepieces · Meade · Misc. · God and Science · SETI · Software · UFO · XEphem
RSS Button

Home | Discussion Forums | Amateur Telescope Making | Post

Be the first pioneers to continue the Astronomy Discussions at our new Astronomy meeting place...
The Space and Astronomy Agora

Forum List | Follow Ups | Post Message | Back to Thread Topics | In Response To
Posted by Robert May on April 21, 2002 03:39:57 UTC

The only thing you really need to do is put the light source on the other side of the KE. It doesn't care really where it is and it can even be a little offset distance wise from the mirror relative to the KE. You can even put it underneath the KE if so desired and that would be a better choice as the form of the errors will minimize the ellipsoid error (ellipsoids have two focii and the source and destination in your present setup will make you do ellipsoids instead of paraboloids!) in the test.
The other thing is that you can also turn around the KE with no problems also. It doesn't matter to the test which way the system tilts or otherwise moves as long as the KE and the slit remain parallel to each other.
As to the eye distance, you are needing to get the entire light cone (same angle as the cone coming from the mirror) into your eye which will probably have a 2-3mm aperture. Anything that will make the entire cone go into the eye will be sufficient. Remember that you are focusing on the mirror, not the KE when you are looking at the shadows on the mirror.

Follow Ups:

    Login to Post
    Additional Information
    About Astronomy Net | Advertise on Astronomy Net | Contact & Comments | Privacy Policy
    Unless otherwise specified, web site content Copyright 1994-2022 John Huggins All Rights Reserved
    Forum posts are Copyright their authors as specified in the heading above the post.
    "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET"
    are trademarks of John Huggins