Re:Re: ATM Aplanats - What would I do with it?

[kwhitefire@juno.com]

Let me get a little more specific, and explain my slight vagueness.  

In addition to being a scientist, I am also an artist.  The Great Orion Nebula is a favorite target of mine for any telescope.  It should appear bright, large, and clear, despite the fact that it is a faint and rather fuzzy object.  The moon is also a favorite.  Craters should have high contrast, the shadows have no color fringes where they meed light.


>...I want something that I can look into, using my eyes.  The image has to 
>look good.

My eyes are excellent, 20/25 and 20/22.  They have slight astigmatism and a little problem with floaters.  I know where the floaters are, and my brain can process around them to an extent.  Looking good means the image is clear and dark, with no added color or curve.  That's as good as my description can get.


>>>This is a vague definition.  We can't help you decide on your design until you 
nail the jello to the wall.  My wife's eyes do not appear sharp - or at least 
she is not very picky in terms of optical performance.  What she 
considers 'good' in a telescope is often unacceptable to me.

What is 'good' to you?

>I also want something that I can attach a camera, and make that same image
>look good on film.

35mm, off the shelf, 400 speed color.  Probably Kodak or Fuji.  I've been known to use old-style Polaroid b&w film and a steady hand.  My first astrophoto was of the Big Bear.  2 minutes long, B setting, camera steadied by a rock attached to the earth.  Hey, it worked!

I want the whole 35mm film to have a consistent quality from edge to edge and in the center.

>>>I won't ask what your defintion of 'good' is again, but what size film do you 
want to cover?  What image quality/resolution do you want in the center?...at 
the very corners?

>I don't want to have to focus at different points to see the edge.  The
>fisheye look is out.

>>>This is still vague.  If you use a short focal length eyepiece...just about 
any design will avoid the 'fisheye look.'  Depending on the field stop of your 
eyepiece, focal length of the eyepiece, the ability of your eye to accomodate 
(focus), and other parameters...what works for you may not work for others.

I like an eyepiece with a comfortable eye relief.  Astronomy is supposed to be relaxing and comfortable (except when the glass needs pushing).  My eye takes 20 minutes to reach its best.  It likes the night.  I like a longer focal length eyepiece, too, because of the image steadiness.  I'm mostly used to a rickety alt-az setup with a 60mm scope mounted on top.  I have an 8"f/6 Newt that's almost done, on a Tex mount.  That should prove better.

>So I'm a firm believer in the Uniscope.  It's that mythical creature we all
>dream about, what a perfect telescope would be.  What is it called?  That's
>what I'll make.  If it's unknown, then I'll invent it.

Please keep us appraised of your progress.  The more objective your design and 
acceptance criteria are...the easier it will be for you to say whether or not 
your scope is good enough.

Tom Krajci
Tashkent, Uzbekistan

Field flatness:  In excess of 1000 inches, + or -.
Coma:  1/8 or less than a Newtonian of the same f/D
Astig:  1/8 or less than the same Newt
f/D:  Somewhere between 10 and 16 is ideal for my eyepiece budget.




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