Ideal Binoculars

John Acorn janature at
Tue Jun 27 23:57:34 EDT 2000

Fellow Butterphiles,

I use the B & L Elite 10X, but not very often for butterflies.  Don't get me
wrong-- they are superb binoculars.  The thing I don't like is that you do
not get to see the butterfly simultaneously in both fields of vision at the
closest focus distance.  Try it for yourself and see.  Your brain tricks you
into thinking you are seeing the bug with both eyes, when in fact you are

The problem lies in the fact that the objective lenses are too far apart,
even on roof prism binoculars, to give a good stereo image at distances of 2
m or less.  It's called "parallax."  The solution would seem to be
close-focusing reverse-Porro binos (the type with the objective lenses
closer than the ocular lenses), but such a thing really doesn't exist as

So... what you do is buy a Nikon 5T close-up lens, and place it infront of
your reverse-Porro compacts.  I use the B & L Custom Compact 9X.  This gives
a superb stereo view, at high magnification.  The only drawback is that this
rig focuses at about arms' length, and not beyond (you have to take off the
5T to check out a bird).  With pracise, this is not too tricky a thing to

Another excellent tool for butterfly watchers is a close-focusing monocular,
most of which focus much closer than any binocular on the market.  Bushnell
used to make a good one, as did Swift.  Right now, however, I think Nikon
may be the only brand available, although perhaps Zeiss still makes one too.
 If you don't mind looking through one eye (which you may be doing already!)
they are superb, and very compact.  I also use the Zeiss "Mini Quick" with
an add-on dioter adjustment lens from a Nikon SLR to make it focus closely.

I have explained this same line of reasoning to the people at Bushnell
Sports Optics, hoping they would cater to butterfliers, as well as a few
other binocular reps.  Bio Quip was at one point thinking of packaging a 5T
and a reverse-Porro together-- perhaps they still are.  I also submitted an
article to American Butterflies on this subject, which was never
acknowledged, let alone published.  All I can say is that anyone who tries
these things likes them.  Hope you do too.

John Acorn
Edmonton, Canada

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