To: Joe Mayenschein 
From: Mark Suchting 
Cc: ATM Mailing List 
Reply-To: Mark Suchting 


At 07:26 AM 22/12/2002 -0600, Joe Mayenschein wrote:
>Ok, personally, myself I have never had a "Problem" with it,
because I have
>never used one.
>
>BUT,,, when holding many many sidewalk sky shows, having one person
>standing below the line of sight is clearly obvious. and they are many feet
>away.

Joe

Pardon me for jumping on the well -worn hobby horse but :

Therein lies the difference between theory and real experience with a true binocular.

I think body heat in front of aperture is a great variable depending on
which way the wind is blowing, how much clothing you have on, is it winter
or summer, which way is the scope pointing , and what altitude etc.  There
is no way to even imagine hard and fast rules about the effect, let alone
write off a particular style of  instrument because of a percieved 
problem.

Most large telescopes, if they have good optics are also capable of
producing Airy Discs that are much smaller than the typical seeing, so
there is some lessening of the effect there. For deep sky observing where
you tend not to be waiting around for that fleeting moment of good seeing
where your telescope can reveal all it is capable of,  `body heat ' will
never be an issue.

In ten years of using my 8" Binoscope I had many wonderful lunar and
planetary views, and countless awesome deep sky ones. My recent experience
with a 20" under good seeing conditions, we never had anything other
than usable  images. I'm not saying that the problem may not be there, but
I have never found it to be a noticeable enough distraction to the awe of
using a binocular telescope.

I heartily applaud what JMI are doing . Whatever they do, they always seem
to do really well, They have apparently been through 11 prototypes before
arriving at a production model.  People  pay $10000 or so for an apochromat
6" Fujinon binocular , so a well thought out binocular with
interchangeability of eyepieces at $4000 is  well positioned in the market
place.

For many people the reality immersion experience of a true binocular will
outweigh a much larger monocular any day.

I really wish JMI well with their project. I think its a momentous occasion
when an experienced telescope manufacturer take on production of Newtonian
binocular . I look forward to using a pair one day.  (  I love the bicycle
handlebars below the eyepieces...I can quite imagine a leisurely `cycle'
through the universe )

~Mark Suchting

--- BBBS/NT v4.00 MP