Re: Televue 85

rmorea@xxxxxxxxxxx wrote: 
Hi!

I originally posted this on sci.astro.amateur, but it may also apply
here since I think this scope is sometimes used by birders, albiet it
is considered a bit too big for easy mobility...  If anyone has
comments, I am interested.

--------------------------------

I just bought a new Televue 85.  Just for the heck of it, I attempted
the
dollar bill test as explained by the Better View Desired webpage.

Basically the test works like this.  Tape a $1 bill to a fence (or
whatever) with the back side facing outward.  Set your scope up to view
it.  Notice with your naked eye that the shading under the word ONE on
the back of the dollar bill is actually a series of closely spaced
lines.  For me, I can distinguish individual lines from about 18 inches
or so.

At 50x, which is a 12mm Radian, I can distinguish these lines from
about 45 feet.  Now, this would seem quite fine to me, and I am
basically satisfied.  But it is less than what was reported for the
Better Views Desired reference scope, a Nikon 78mm Fieldscope, which
resolved the lines from about 75 feet at 56x.

Reasons could be anything from the reviewer has better eyes, he is a
better observer, he used a newer dollar bill, his standard for *seeing*
the lines is different from mine, the difference between 50x and 56x,
or his scope is better than mine.

Strangely, it doesn't bother me so much if I have worse eyes but a
worse scope would be terrible!  OK, so thats not logical.  Has anyone
else tried this test with a TV-85?  Care to share the results?

It's night, and I can't make 75 feet indoors. From 45 feet, standing at the tripod, I can tell that there are lines at 33 power (12 mm), but I can't count them. At 67 power (6mm, my next choice), I can count them. My objective is an 80mm f/4 by Baytronix from eBay. The eyepieces are orthoscopics from Edmund. I hope that helps.

Jerry
--
Engineering is the art of making what you want from things you can get.
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