Re: astronomical vs. terrestial telescopes

[brian whatcott <inet@INTELLISYS.NET>]

At 16:43 1/25/99 -0600, you wrote:
> ... in lab we measure experimentally the magnification of a telescope
> by holding up a ruler at arm's length and looking through the telescope
> with the other eye. I've tried to do similar things with a microscope, but
> it's hard to do, as are alternatives like trying to draw the size of the
> image on the eyepiece. Is there a workable way to experimentally estimate
> the magnification of an approximately 2X microscope (suitable for a
> low-cost introductory lab)?
>
> Dr. Carl E. Mungan

One method which may be adaptable to Carl's purpose, is the graticule
line placed at the focal plane of the converging eyepiece.
  Then an object may be moved by a measured distance (with a micrometer
screw in the case of a microscope slide, or perhaps with a ruler in the
case of a telescope) and the effect of a known displacement observed in
the image plane.
(A chinese micrometer costs about $10 here)

Brian Whatcott
brian whatcott <inet@intellisys.net>
Altus OK