Archive-name: birds-faq/optics
Last-modified: 8 August 1994
Posting-frequency: monthly

        Frequently Asked Questions about Optics for Birding
                             August 1994

| This is the list of Frequently Asked Questions (FAQ) about optics for
| birding. This FAQ started as a monthly posting to the Internet news
| group rec.birds. I now post it monthly to rec.birds and the BIRDCHAT
| mailing list on or about the 15th of the month.
| 
| Send any comments, suggestions, or additions to Ed Matthews
| <edm@aib.com>. I do not receive rec.birds or BIRDCHAT, so I don't see
discussion on the net. Please forward any appropriate mail to me.

Notes
=====

1. Hey, you guys missed some typos last month!

2. Can somebody send me a discussion of various kinds of lens glass:
   e.g., ED, fluorite, etc.

3. Can anyone contribute a discussion of the various prisms?  Porro
   vs Roof, etc.

Summary of Changes Since Last Publication
=========================================

[As always, change bars '|' mark significant changes]

0.   Minor edits.
0.   Now posted to BIRDCHAT on monthly basis.
2.15 Hopefully now written in more readable English :)
2.17 New info on finding birds quickly
5.   New info on National Camera Exchange

Table of Contents
=================

1. General Advice
2. Common Questions About Optics
  2.1 What does 7x35 mean?
  2.2 How do I chose a magnification level?
  2.3 What is field-of-view?
  2.4 What about rubber armoring?
  2.5 Can I use binoculars and scopes with eyeglasses?
  2.6 What is eye relief?
  2.7 How do I judge comparable binoculars?
  2.8 What about fixed versus zoom eyepieces for scopes?
  2.9 What about 45 degree eyepieces for scopes?
  2.10 Can I take pictures through a scope?
  2.11 How close should I be able to focus?
  2.12 Which inexpensive binoculars would you recommend to a beginner?
  2.13 What does the endorsement of the National Audubon Society mean?
  2.14 How should I clean my lenses?
  2.15 What should I know about lens coatings?
  2.16 How can I hold my binoculars steady?
  2.17 How can I find birds quickly with my binoculars?
  2.18 What factors affect brightness in optical instruments?
  2.19 What other factors should I consider in buying binoculars?
3. Supports
  3.1 Tripods
  3.2 Monopods
  3.3 Finnsticks
  3.4 Shoulder Stocks
  3.5 Window Mounts
4. Ratings
  4.1 Better View Desired (Scopes and Binoculars -- November 1993)
  4.2 Living Bird (Binoculars -- Autumn 1992)
  4.3 British Birds (Owner Survey, Binoculars and Scopes, July 1991)
  4.4 Living Bird Quarterly (Scopes -- Autumn 1990)
5. Sources for Optical Equipment
6. Useful Reference Material
7. Contributors

1. General Advice
=================

Don't buy any optical equipment without first field testing it,
especially if you wear glasses.  Go to a popular birding spot and ask
to try various scopes and tripods.  This is the only way to determine
individual preferences such as weight, balance, and desirable
magnification level.

Owners of most tripod brands report loose parts and some report rust.
Tripods, like any other equipment with moving parts, require periodic
tightening and cleaning.

A good strap on a scope or binoculars increases comfort dramatically.
The new breed of neoprene straps from OP/TECH come highly recommended.
They are available from most optics merchants and camera shops.

2. Common Questions About Optics
================================

2.1 What does 7x35 mean?

The first number (7) is the magnification (or power).  The second (35)
is the size in millimeters of the objective lens (or aperture).  The
objective lens is the large lens through which the light first enters
the binocular or scope.

Objective lens size is a key factor in how much light enters the
instrument.  To determine the relative brightness of an instrument, divide
the objective lens size by the magnification (e.g., 35mm/7 = 5mm).
Optical instruments cease to be brighter when this measure, called the
exit pupil, exceeds the size of your pupil.

Apparently, as you age, your pupil does not dilate as much as when you are
younger.  By age 40, your pupil dilates to a maximum of about 5mm.  Buying
binoculars with a larger exit pupil is a waste of money.

If exit pupil were the only factor in brightness, your choice would be
easy.  However, the quality of the glass and its coatings (q.v.)  play a
large part in determining brightness.  You will find that good 10x40
(4mm exit pupil) binoculars are generally brighter than cheap 7x35 (5mm
exit pupil) binoculars.

Birders who try to see pelagic birds on an active ocean find their
binoculars move around a lot with respect to their eyes, especially if
they wear eyeglasses.  An over large exit pupil helps keep a bird in view
as they bounce around on the tossing deck, with the binoculars in one hand
and the other hand holding onto the boat itself.

2.2 How do I chose a magnification level?

The lower the magnification (power), the shorter the effective range of
the instrument.  As a payoff, you get a brighter image and a wider
field-of-view.  The higher the power, the harder the instrument is to
hold steady, the less bright the image, and the narrower the
field-of-view (q.v.).

For binoculars, common magnification levels are 7x, 8x, and 10x.  Good
quality optics are generally more important than magnification level.

For scopes, the most popular range is between 20x and 40x.  Distortion
from heat shimmer becomes a big factor over 40x.  Lower than 20x limits
the useful range of the scope.

The power of an instrument is the focal length of the main objective
divided by the focal length of the eyepiece.  For instance, a scope with
a main objective of 900mm focal length and eyepiece of 30mm focal length
is 30x (900/30).

In very simplistic terms, the focal length of a simple, thin lens is the
distance from the lens that it focuses the object. For example, a lens
with a 30mm focal length would focus its image 30mm behind the lens.

2.3 What is field-of-view?

Binoculars typically have a label that expresses field-of-view (FOV) in
degrees and/or width at a given distance.  Expressed in degrees, FOV means
that portion of a circle (360 degrees) visible at a certain distance.

In the US, we calculate FOV at a distance of 1000 yards (923m).  Typical
FOV at 1000 yards ranges between 5 and 8.5 degrees, which corresponds to
a FOV range of 263 to 446 feet (81 - 137m). [How is FOV expressed in
countries other than the US?]

In many cases, the actual FOV may be markedly different than what the
manufacturer says it is.

To compare the FOV of binoculars with different magnification levels,
compute the "apparent FOV".  This is the actual FOV times the
magnification.  Typical values range from 45 to 75 degrees with most
being between 50 and 65.

Other things being equal, wider FOV is generally better than narrower
| FOV for helping you find birds more easily. Of course, other things
seldom are equal, and you generally must pay for wide FOV some other
way: lower resolution, lower magnification, less eye relief, greater
weight, or higher cost.

2.4 What about rubber armoring?

Binoculars and scopes are sometimes clad in rubber -- this is known as
rubber armoring.  Rubber armoring provides protection against corrosion
and dirt, helps cushion blows to the instrument, and gives a less
slippery surface to grip.  Armoring adds a little weight and may require
maintenance with a rubber preservative.  Many feel rubber preservatives
leave a greasy feeling.

2.5 Can I use binoculars and scopes with eyeglasses?
 
You certainly can; however, DO NOT BUY BINOCULARS OR SCOPES WITHOUT
TESTING THEM WITH YOUR GLASSES.  Some people like to use their
binoculars without their glasses. There is no harm in this. However, if
you have astigmatism, you need your glasses to help you focus, even with
the binoculars (which only increase magnification).

People who wear eyeglasses often have trouble with scopes and
binoculars.  Try several models with your glasses.  The critical factor
if you wear glasses is eye relief (q.v.). Look for eye relief of at
least 15mm.  Since eye relief is a property of eyepiece design, you
cannot change the eye relief of binoculars.  Several scopes offer
optional long-relief eyepieces -- Kowa's are excellent. One exception is
the Bausch & Lomb Elite scopes with fixed lenses; they come with
long-relief eyepieces as standard equipment.

2.6 What is eye relief?

Eye relief is the distance between the eyepiece and your cornea when you
are seeing the full illuminated circle of the image, the sensation of
"looking through" the scope or binoculars.

You can determine empirically the eye relief of binoculars by holding
them steady in a shaded location pointed at a bright sky or surface.
Hold white paper behind the eyepiece and you will see a bright disc of
light on the paper.  This is the exit pupil as discussed earlier.  Move
the paper until the disc is sharpest; this is the precise location of
the exit pupil in space. The distance between the eyepiece and the paper
is the eye relief.

If you wear glasses, eye relief is critical since you must have enough
room to get your glasses between the lens and the focal plane.  Even if
you do not wear glasses, a reasonable amount of eye relief helps keep
the instrument far enough from the eye for comfort. However, high eye
relief designs may give non-eyeglass wearers the sensation that they
need to move their eyes far back from the eyepiece.

In general, shorter focal length eyepieces have shorter eye relief. High
eye relief designs are usually more expensive. Also, higher
magnification generally means less eye relief; scope users may have
noticed this in changing eyepieces. Many eyepieces in wide-angle
binoculars have low eye relief as a consequence of their design,
something to remember and test if you are considering buying a
wide-angle binocular.

The ABA catalogs (q.v.) are good about listing eye relief figures for
most eyepieces and state what they consider minimum.

Celestron [Vixen in Europe] (and perhaps other astronomically oriented)
scopes have optional Barlow lenses that may be of interest to eyeglass
wearers.  A Barlow lens is a long metal tube that attaches instead of
the eyepiece.  The eyepiece goes onto this tube, thus extending the
physical length of the scope and effectively increasing the focal length
of the objective lens. The beauty of the Barlow lens is that it
increases power (about 2x) while letting you continue to use the same
eyepiece with which you are comfortable, a big bonus for eyeglasses
wearers. A couple of readers recommend the Barlows from Astrophysics.

Drawbacks are that the overall length of the scope is increased,
increasing the chances of damage in the field and making the scope a bit
more awkward. Barlow lenses are not very common, nor are they suitable
for quick changes in the field.  Still, in a fixed setting such as nest
watching, the fact you can double the power and preserve the eye relief
is significant.

Also, several scope manufacturers offer long eye relief eyepieces by
various names. Celestron/Vixen calls their 20mm eye relief eyepieces LV
(Long View).  

2.7 How do I judge comparable binoculars?

When judging binoculars, you should know what properties the power and
aperture (e.g., 7x50) fix, as opposed to other parameters that are the
consequence of good design (e.g., long eye relief).  If you know the
power and aperture, the following are fixed, and the most expensive pair
of that type will have the same value as an inexpensive pair:
 
  Exit pupil diameter or "apparent brightness"
  Depth of field, i.e., range in which objects appear in focus at given
distance
  Faintest STARS visible, determined by aperture only (indep. of power)
 
Optical quality and design affect:
 
  Eye relief (tends to be longer in lower power binocs)
  Image contrast (because of number and quality of coated surfaces)
  Apparent field of view (can't be large if eye relief is long)
  Image sharpness across field (harder in wide field binocs)
  Closest focus (tends to be closer in low power binocs)

Here are several examples: 7x35's are about as "bright" as 8x40's.  Two 7x50's
could have very different eye relief.  If one pair has a wide apparent field,
it probably has shorter eye relief.  A large pair of 20x70's will have
a less bright image than a small pair of 8x32's.  That same 20x70 probably
does not focus as close as the 8x32.

2.8 What about fixed versus zoom eyepieces for scopes?

Fixed magnification eyepieces tend to give a crisper and brighter image.
Zooms can be useful, but unless you spend a lot of money, they can be of
lesser quality than fixed lenses.  Some birders prefer interchangeable
fixed lenses (e.g., a 25x lens and a 40x lens) to a zoom.  Zooms on the
expensive scopes (e.g., Kowa) are excellent.

2.9 What about 45 degree eyepieces for scopes?

They are not hard to use when you get used to them and are preferable
for watching flying birds, especially migrating raptors.  If you're
tall, you can use a slightly shorter tripod.  If you're short, the lower
scope gives more opportunity for somebody to step in your way.  A
drawback is that the eyepiece is angled up into the rain and blowing
dust.

2.10 Can I take pictures through a scope?

General consensus is that if you want to take professional pictures, don't
use your scope.  It requires a really steady (heavy) tripod and the combo
of scope and camera is heavy and awkward.  Focusing is difficult and close
focusing is not generally possible. Scopes usually have a fixed, small
aperture (typically f11). This means that you must adjust exposures by
varying the shutter speed. With a small aperture, and a fast enough
shutter speed to keep the bird from blurring, you must use fast film,
even in bright sun. In early morning and late evening, or in shady
woods, you simply won't have enough light to take a good picture.  Some
scope/camera combinations also have problems with vignetting: the rim of
the scope is visible in the picture as a dark, fuzzy ring around the edge.

[Paraphrased from the Canon EOS FAQ on rec.photo by Bob Atkins]

  In general, scopes are too slow and their focal lengths are too long.
  The longer the focal length, the steadier you must hold the lens and
  the more atmospheric effects will degrade the image. The only scopes
  capable of yielding high quality images are the fast, short focal
  length, apochromatic refractors. For example, TeleVue makes a 500mm f5
  apochromatic telescope using Fluorite lens elements. It makes a very
  good lens (manual focus, fixed aperture), but costs US$1700, weighs
  10lbs+ (4.5k+) and is about 36" (92cm) long. While not easy, you can
  use it in the field with a heavy tripod.  Its performance as a lens is
  similar to the best telephoto lenses; however, it has several
  drawbacks.  It has no autofocus; you cannot stop it down; and it is big
  and heavy.

2.11 How close should I be able to focus?

[Paraphrased from _The Complete Birder_, Houghton Mifflin, Boston, 1988,
by Jack Connor]

Binoculars with close-focus are essential for woodland birding.  You can
visually separate several problematic pairs of small birds only at close
range:  Carolina and Black-capped Chickadees; Sedge and Marsh Wrens;
Mourning and Connecticut Warblers; Le Conte's and Sharp-tailed Sparrows;
Cassin's and Botterei's Sparrows; and many others.

Fortunately, you can test close-focus in a store.  Find the closest spot
on the floor you can see sharply through the binoculars, then count your
paces as you walk to it.  For an accurate test, first adjust the
dioptric-compensation ring for the difference in strengths of your two
eyes. Without first doing this, your test will be inaccurate.

A close-focus range of 15 to 18 feet (5 to 5.5m) is the least you should
accept.  If you like chasing sparrows and warblers, you'll be happier
with a minimum range of about 10 feet (3m).  Depending on your eyes, you
can find binoculars with close-focus ranges down to 6 feet (2m).

2.12 Which inexpensive binoculars would you recommend to a beginner?

Many people consider the Bushnell Birder 7x35 a great buy at US$75 or under.

2.13 What does the endorsement of the National Audubon Society mean?

The NAS has licensed their logo to certain manufacturers and the logo
appears on certain optical products. The appearance of the logo does not
constitute any endorsement by NAS.  The logo presumably indicates that
the product is targetted at birders; however, it does not mean that it
is any better than competing products from other manufacturers.

2.14 How should I clean my lenses?

[From a Celestron manual:] "Always determine whether or not your
telescope needs cleaning. Specks of dust or pieces of lint do not impair
the visual or photographic performance of your telescope, but excessive
cleaning can cause small scratches which harm performance more than lint
or dust. These scratches cause light scattering, which is VERY harmful
to optical performance. Professional telescopes used nightly, only need
cleaning every six months or so."

A good cleaning solution is a mixture of isopropypyl alcohol and
distilled water with a few drops of biodegradable washing detergent. Do
not use breath or saliva.  Cotton balls of natural cotton are best.
Never clean in circles to prevent making scratches all over the optics.
Never rub or apply pressure! Use fresh cotton balls often. Go from the
center to the edge of the lens; take another piece of cotton and repeat!

To avoid frequent cleanings, always store your lens with the caps on.

2.15 What should I know about lens coatings?

Low-reflection coatings increase the light transmitted through
| binoculars by increasing contrast, reducing glare, and eliminating
| reflections.  For best results, all glass surfaces where the beam of
light moves from air into glass or from glass into air should be coated.
Cheap binoculars sometimes only have coatings on the outside surfaces,
in an attempt to impress and confuse the gullible buyer.

The best coatings are called "multi-coatings", or something similar;
they are better simply because a multi-coated surface reflects less
| light than one with a conventional coating. You can notice the
| difference between single- and multi-coatings particularly when viewing
birds in shade when the field of view also includes brightly lit objects
(i.e., extreme contrast).

It is hard to tell what surfaces of a binocular are coated, and with what
kind of coatings, just by looking at them. For this reason alone, you
should buy from a well-respected manufacturer and from a reputable dealer.

2.16 How can I hold my binoculars steady?

[Jay Freeman offers this tip in Ronnie Kon's Purchasing Amateur
Telescopes FAQ on sci.astro.]

Most people hold a binocular with one hand on each side of the body --
roughly where the prisms are. The hands are directly left and right of
the center of gravity of the instrument.

For most people, there is a better position. Hold the binocular as
described above. Slide your hands toward your face, until only your
pinky and ring fingers (third and fourth) are curled around the back
end of the binocular body. The binocular will feel a little nose-heavy,
because you are supporting it behind its center of gravity.

Curl each thumb up as if you were making a fist, and flex your hands so
that the second bone in from the tip of your thumb is pressed against
your cheekbone. Finally, curl the first and middle fingers of each hand
around the corresponding binocular eyepiece. You will have your hands
as though you are peering into a bright window at night. Your hands
will make a solid structural connection between the body of the
binocular, through your hands and thumbs, to your face, and markedly
improves how steadily you can hold the instrument.

If this out-of-balance position becomes tiring, move one hand out to the
objective end of its side of the binocular, so that you are supporting
the instrument on opposite sides of its center of gravity.  When you get
tired, switch hands.

2.17 How can I find birds quickly with my binoculars?

Here are some tips from experienced birders:

  1. Memorize how you turn the focus wheel to focus closer or farther.
  2. Remember at all times how far away you last focused.
| 3. After looking at a bird, refocus for where you expect the next bird.
|    In the woods, this is close.  On the beach, this is farther out.
  4. Start focusing before the binoculars get to your eyes.
| 5. Make a mental note of where the bird is: "third branch to the right
|    against yellow leaves."  Vegetation looks different with and without
|    binoculars.
| 6. Keep looking at the bird while raising the binoculars into your line
|    of sight.
  7. Practice, practice, practice

2.18 What factors affect brightness in optical instruments?

Have you noticed that the warbler in the bush at dusk that you can see
with binoculars practically disappears without them?  The effect is
profound and many people believe this is because binoculars and
telescopes act as "light buckets" that collect light over a large area,
effectively enlarging their eyes.

This is true, but the magnification of the lens spreads the light over a
larger area and the apparent brightness "per square degree" is no more
than with the naked eye.  What is really happening is that the lens is
enlarging the object without making it fainter.

Higher quality optics increase apparent brightness by eliminating
reflections.  This effect can be substantial, but probably does not
cause a dramatic difference in brightness between two pairs of
binoculars.  The dominant factor is the exit pupil (q.v) which, if
smaller than the diameter of your pupil, will decrease brightness.
Another factor is contrast, which does not increase brightness but does
give the appearance of a brighter view. Lens coatings (q.v.) generally
improve contrast.

2.19 What other factors should I consider in buying binoculars?

You should consider how you are going to use and treat them. Consider
the following questions:

o If you have an expensive pair of binoculars, will you be afraid to take
  them with you?

o Do you plan to store the binoculars in your car so they will always
  be with you?

o Can you carry them easily when hiking, biking, or cross-country skiing?
  Perhaps you want a second pair for this?

o Do you plan to use them in very humid/wet environments?

o Do the binoculars fit your hands? Binoculars and people come in 
  different shapes and sizes.

o Do the lens caps remain attached? Can you remove them easily?

3. Supports
===========

Supports for birding with binoculars and scopes come in several forms:
tripods, monopods, Finnsticks, shoulder stocks, and window mounts.

3.1 Tripods
===========

Owners of most tripod brands report loose parts and some report rust.
Tripods are like any other equipment: they require some preventative
maintenance.  The large majority of US readers use one of two tripods,
the Bogen 3021 or the Davis & Sandford RTS. Gitzo also makes fine
tripods which are popular among professional photographers.

Here's a tip for all you tripod thunkers. To minimize the thunk of the
tripod when you open it, hold it horizontally, then pull out and lock the
legs. The birds and your fellow birders will appreciate it.

If you have problems with vibration, you can always hang a heavy object
underneath your tripod to give it more stability and quicker damping
time.  Astronomy catalogs sell aluminum and rubber gadgets that reduce
vibration times by about 3x for about US$40.

Bogen (Manfrotto outside the US)

Model 3021 (Manfrotto 55) is most popular with birders; lesser models
are not sturdy enough; larger models are overkill.  With the micro-fluid
head, it weighs about 8 pounds (3.5k) without scope, so it requires a
strap.  However, the weight makes for a steady scope in the wind.  The
quick release plate for the micro-fluid head is nice, especially for
switching between scope and camera.  The quick-release leg levers are
handy, but take some strength to operate and have a reputation for
coming loose. A few birders report tripod collapse as a result. The
levers can catch twigs, hair, and binocular straps. Legs can open
noisily if not careful. Good height for tall birders.  Replacement parts
are readily available.  With proper maintenance, owners are generally
happy with this tripod.

Davis & Sanford (Tiffen)

Model RTS is no frills, solid, lightweight (4.75 lbs, 2.2k), and fast to open
because of its twist-to-unlock legs.  Is not as tall as Bogen 3021.
[Editor's note: I'm 6'3" (2m) and the Bogen is a better fit.]  Owners
find this tripod plenty sturdy even with heavy scopes.  The pan-head is
very simple -- twist the pan-arm to loosen and twist back to tighten in
place.  The quick change screw for quick release mounting is nice.
Owners seem to be universally happy with this tripod.

Gitzo

While primarily aimed at professional photographers who need stability
for monster lenses (400mm+), Gitzo tripods have found some favor among
birders.  Model 341 (the Inter Pro Studex Rapid) is solid (7 lbs, 3.2k),
good for tall birders, and well built.  The Bogen fluid head fits this
tripod.  Drawbacks are that it is expensive (around US$300) and long
(29", 75cm) when collapsed.

3.2 Monopods

A monopod is not a replacement for a tripod.  However, a monopod is an
option when weight and bulk are factors.  When I travel by air, I pack a
monopod, scope, and binocs into my briefcase along with the appropriate
field guides, leaving my hands free for luggage and portable computer.
Monopods lack stability (especially in the wind) and have only limited
height (I perch mine on a rock where possible).
 
3.3 Finnsticks
 
A finnstick is literally a stick, usually with a fork at one end, which
you use to hold your binoculars at eye-level, allowing you to keep your
arms down.  Consequently, you keep your view steadier for longer periods.
Finnsticks are useful in any endurance situation: hawk watching, sea
watching, and pelagic trips. 
 
These sticks originated in Finland where they are called staijikeppi
(pronounced: stah-yeeh kep-peeh). Most finnsticks are homemade (since
they apparently have a proclivity for getting lost) from branches 1.5-2
inches (4-6cm) in diameter, 2-3 feet (60-100cm) in length, with a
natural fork in one end. This fork, with perhaps a little carving, fits
under the center barrel of the binoculars.

3.4 Shoulder Stocks
 
A shoulder stock is device similar to the stock of a gun, on which you
mount a scope or camera.  Some people prefer a shoulder stock for its
mobility and portability.  They are excellent for following the path of a
moving bird; however, the scope is only as steady as your arm and your arm
will get tired quickly.

3.5 Window Mounts

Several manufacturers make scope mounts that slide over and fasten to a
car window. These are useful for birding impoundments and fields
accessible by car.  Although very handy, they transfer all vibrations
from the car to the scope, so you have to turn off the car and they also
can take infuriatingly long to attach to the window. An alternative is a
small (usually homemade) bean bag that rests on top of the window (or
car roof, boulder, limb).  See the Dec 1992 _Birding_ for more details.

4. Ratings

4.1 Better View Desired (Scopes and Binoculars -- November 1993)
==============================================================

[This list also contains recommdations from the February 1994 issue.]

The following selections come from the November 1993 issue of _Better View
Desired_, Stephen Ingraham's newsletter devoted to evaluating birding
optics.  These selections are in two categories: Reference Standard,
products that set the performance standard for their class; and, Best Buy,
products with outstanding performance at an affordable price.

Reference Standard: the performance standard for its class

   Compact Binoculars            : Bausch & Lomb Custom 7x26
   Mid-sized Binoculars          : Optolyth Alpin 8X30
   Full-sized 7x & 8x Binoculars : Zeiss 7X42
   High-power Binoculars         : Celestron 9.5X44ED
   50-60 mm Spotting Scopes      : Nikon Fieldscope ED
   70-80 mm Spotting Scopes      : Tel Vue Pronto
   Catadioptric Scopes           : Questar Birder
 
Best Buy: outstanding performance at an affordable price

   Mid-sized Binoculars          : Celestron Ultima 8x30
   Full-sized 7x & 8x Binoculars : Swift Ultralite 8x42
   High-power Binoculars         : Swift Ultralite 10x42
   50-60 mm Spotting Scopes      : none
   70-80 mm Spotting Scopes      : Celestron S80+

   Compact Binoculars            : Bausch & Lomb Legacy 8x24
                                   Minolta Compact 8x23
                                   Nikon Travelite 8x23
                                   Pentax UCF 8x24
                                    Swift Micron 8x25
   Mid-sized Binoculars          : Celestron Ultima 8X30
   Full-sized 7x & 8x Binoculars : Swift Ultralite 8X42
   High-power Binoculars         : Swift Ultralite 10X42
   50-60 mm Spotting Scopes      : none
   70-80 mm Spotting Scopes      : Celestron S80+
   Catadioptric Scopes           : Celestron C90


Products of Special Merit: not quite top products, but certain outstanding
characteristcs.

   Compact Binoculars            : Nikon Diplomat 10x25
   Full-sized 7x & 8x Binoculars : Swift Audubon 8.5X44 (exceptional
      resolution and ease of view at a very reasonable price)
   Zuka Scope (hand holdable Newtonian Telescope)
   Celestron C5 (perhaps the highest resolution and brightness of any
      spotting scope currently available in a moderately compact
      package. The ultimate long distance scope.)

4.2 Living Bird (Binoculars -- Autumn 1992)
===========================================

[Thanks to Sid Johnson for this report from "Binocular Quest", _Living
Bird_, Autumn '92, T. Culver and H. Gerhart.  All prices in US dollars.]

                                Suggested
                                   List   Prism
         Model                  Price $US Type       Armor?   Warranty

Over US$800:

* Bausch & Lomb Elite 10x42       $1,956   Roof        Yes   Limited Lifetime
* Bausch & Lomb Elite 8x42        $1,900   Roof        Yes   Limited Lifetime
* Bausch & Lomb Elite 7x36        $1,704   Roof        Yes   Limited Lifetime
* Leica Ultra 10x42 BA            $1,590   Roof        Yes   Lifetime
* Leica Ultra 8x42 BA             $1,590   Roof        Yes   Lifetime
  Nikon Classic Eagle 8x40 DFC    $1,232   Roof        No    25-year Limited
* Zeiss Dialyt 10x40 B/GAT        $1,250   Roof        Yes   Lifetime
* Zeiss Dialyt 7x42 B/GAT         $1,215   Roof        Yes   Lifetime

US$500-US$800:

  aus Jena Luxus 10x40              $775   Roof        No    Limited Lifetime
  Bausch 7 Lomb Custom 10x40        $528   Porro       Yes   Limited Lifetime
  Nikon Execulite 9x30              $567   Roof        No    25-year Limited
* Nikon E CF HP 8x30                $512   Porro       No    25-year Limited
* Optolyth Touring 10x40            $608   Roof        Yes   Limited Lifetime
  Swift Audubon 7x35                $600   Roof        Yes   Lifetime

US$200-US$500:

  Celestron Ultima 10x42            $350   Porro       No    Limited Lifetime
  Celestron Ultima 8x32             $350   Porro       No    Limited Lifetime
  Minolta Weathermatic 7x42         $406   Roof        Yes   25-year Limited
  Optolyth Alpin 10x40              $360   Porro       Yes   Limited Lifetime
  Optolyth Alpin 7x42               $360   Porro       Yes   Limited Lifetime
  Optolyth Alpin 8x30               $298   Porro       No    Limited Lifetime
  Pentax DCF 8x42                   $375   Roof        No    Original Owner
  Pentax PCF 7x50                   $220   Porro       No    Original Owner
  Pentax PCF 7x35                   $200   Porro       No    Original Owner
  Redfield WP 10x50                 $407   Roof        Yes   Limited Lifetime
  Redfield WP 7x35                  $361   Roof        Yes   Limited Lifetime
  Swift Audubon 8.5x44              $399   Porro       No    Lifetime

* Swift Ultra Lite 8x42 ZWCF        $345   Porro       Yes   Lifetime
  Swift Egret 10x42 HCF             $288   Roof        Yes   Lifetime

Under US$200:

* Bushnell Birder 7x35               $75   Porro       No    Limited Lifetime
  Minolta Standard 7x35             $141   Porro       Yes   25-year Limited

Compacts:

* Bausch & Lomb Custom Compact 7x26 $457   Rev. Porro  No    Limited Lifetime
  Leica 10x25 BCA                   $645   Roof        Yes   Limited Lifetime
  Leica 8x20 BCA                    $615   Roof        Yes   Limited Lifetime
  Minolta Pocket 7x21               $137   Rev. Porro  No    25-year Limited
  Minolta Compact 8x23              $132   Rev. Porro  No    25-year Limited
  Nikon Travelite III 9x25          $156   Rev. Porro  No    25-year Limited
  Pentax UCF 8x24                   $160   Rev. Porro  No    Limited Lifetime
  Redfield 8x24                     $210   Roof        No    Limited Lifetime
  Swift Micron 8x25 CF              $120   Rev. Porro  No    Limited Lifetime
  Zeiss Design Selection 8x20 BT    $530   Roof        No    25-year

* Top rated

                                                                        Play
of
                                 Interpupil       Good for    Weight     Focus
    Model                         Distance       Eyeglasses? (ounces) 
(degrees)

Over US$800:

* Bausch & Lomb Elite 10x42   2-3/16" - 2-7/8"       2         28.1       400
* Bausch & Lomb Elite 8x42    2-3/16" - 2-7/8"       1         29.1       400
* Bausch & Lomb Elite 7x36    2-3/16" - 2-7/8"       1         25.4       400
* Leica Ultra 10x42 BA        2-3/16" - 2-7/8"       2         32.0       330
* Leica Ultra 8x42 BA         2-3/16" - 2-7/8"       2         32.0       330
  Nikon Classic Eagle 8x40    2-1/8" - 2-13/16"      2         28.2       190
* Zeiss Dialyt 10x40 B/GAT    2-3/16" - 3"           2         26.4       330
* Zeiss Dialyt 7x42 B/GAT     2-1/4" - 2-15/16"      1         28.2       450

US$500-US$800:

  aus Jena Luxus 10x40        2-3/16" - 2-7/8"       3         24.6       270
  Bausch 7 Lomb Custom 10x40  2-1/4" - 2-13/16"      2         30.9       460
  Nikon Execulite 9x30        2-3/16" - 2-7/8"       4         16.7       630
* Nikon E CF HP 8x30          1-7/8"  - 2-7/8"       2         20.0       330
* Optolyth Touring 10x40      2-1/8" - 3"            2         24.0       410
  Swift Audubon 7x35          2-1/4" - 3-1/16"       2         21.0       460

US$200-US$500:

  Celestron Ultima 10x42      2" - 2-7/8"            2         19.7       360
  Celestron Ultima 8x32       2" - 3"                2         17.4       370
  Minolta Weathermatic 7x42   2-1/4" - 2-7/8"        1         29.1       270
  Optolyth Alpin 10x40        2" - 2-3/4"            4         18.2       690
  Optolyth Alpin 7x42         2" - 2-3/4"            2         18.1       690
  Optolyth Alpin 8x30         2" - 2-3/4"            4         14.9       690
  Pentax DCF 8x42             2-1/4" - 2-7/8"        2         31.0       360
  Pentax PCF 7x50             2-3/16" - 2-3/4"       2         31.8       590
  Pentax PCF 7x35             2-3/16" - 2-3/4"       3         24.3       560
  Redfield WP 10x50           2-3/8" - 3-1/16"       3         28.6       170
  Redfield WP 7x35            2-5/16" - 3-1/16"      2         20.5       170
  Swift Audubon 8.5x44        2-1/8" - 3-1/4"        2         28.9       460
* Swift Ultra Lite 8x42 ZWCF  2" - 2-15/16"          2         21.0       370
  Swift Egret 10x42 HCF       2-1/4" - 2-13/16"      4         18.3       320

Under US$200:

* Bushnell Birder 7x35        2-3/16" - 2-7/8"       3         18.8       460
  Minolta Standard 7x35       2-3/16" - 2-13/16"     3         26.8       270

Compacts:

* B&L Custom Compact 7x26     2-1/4" - 3-1/8"        2         11.5       370
  Leica 10x25 BCA             1-1/4" -  3-1/4"       4          8.8       740
  Leica 8x20 BCA              1-1/4" -  3-1/4"       4          8.1       740
  Minolta Pocket 7x21         1-3/8" -  2-3/4"       4          9.7       350
  Minolta Compact 8x23        2-1/4" - 2-7/8"        4          8.8       340
  Nikon Travelite III 9x25    2-1/8" - 2-7/8"        4          9.4       350
  Pentax UCF 8x24             2-3/16" -  2-15/16"    4          9.9       590
  Redfield 8x24               1-3/8" - 3-1/16"       4          9.6       270
  Swift Micron 8x25 CF        2-1/4" -  2-13/16"     4         10.1       740
  Zeiss Design Selection 8x20 1-1/4" -  2-7/8"       4          6.4       350

* Top rated        Numeric Ratings: 1 to 5, 1 is best


                                                 Optical    Min.    Field of
                                 Focus  Bright-  Perfor-   Focus    View at
         Model                    Feel   ness     mance    Dist.      230'  
Fog
Over US$800:

* Bausch & Lomb Elite 10x42        1       2       1        11'      23.8'   
N
* Bausch & Lomb Elite 8x42         1       1       1      10.5'      27.5'   
N
* Bausch & Lomb Elite 7x36         1       1       1         5'        30'   
N
* Leica Ultra 10x42 BA             1       2       1        14'        20'   
N
* Leica Ultra 8x42 BA              1       1       1        12'        20'   
N
  Nikon Classic Eagle 8x40 DFC     1       3       2      14.5'      27.5'   
N

* Zeiss Dialyt 10x40 B/GAT         2       3       1        15'        20'   
N
* Zeiss Dialyt 7x42 B/GAT          1       1       1       9.5'        30'   
N

US$500-US$800:

  aus Jena Luxus 10x40             1       3       2        18'        20'   
N
  Bausch 7 Lomb Custom 10x40       1       3       2        12'        20'   
Y
  Nikon Execulite 9x30             1       5       2        11'      22.5'   
Y
* Nikon E CF HP 8x30               1       2       1        11'      32.5'   
Y
* Optolyth Touring 10x40           2       3       1        16'      27.5'   
Y
  Swift Audubon 7x35               2       2       2        10'        20'   
N

US$200-US$500:

  Celestron Ultima 10x42           1       2       2        15'      23.8'   
Y
  Celestron Ultima 8x32            2       4       3        12'        30'   
Y
  Minolta Weathermatic 7x42        1       3       3        12'        25'   
N
  Optolyth Alpin 10x40             1       3       3        14'        25'   
Y
  Optolyth Alpin 7x42              1       5       3        27'        25'   
N
  Optolyth Alpin 8x30              1       5       3        13'      32.5'   
Y
  Pentax DCF 8x42                  1       5       3        24'      27.5'   
N
  Pentax PCF 7x50                  2       1       3        15'      22.5'   
Y
  Pentax PCF 7x35                  2       3       4         7'        25'   
Y
  Redfield WP 10x50                2       4       3      24.5'      22.5'   
N
  Redfield WP 7x35                 2       4       3      10.5'        25'   
N
  Swift Audubon 8.5x44             1       3       2      10.5'     31.25'   
Y
* Swift Ultra Lite 8x42 ZWCF       1       2       2        16'        20'   
N
  Swift Egret 10x42 HCF            1       5       3        14'        25'   
N

Under US$200:

* Bushnell Birder 7x35             2       2       3        13'      22.5'   
Y
  Minolta Standard 7x35            2       3       3      12.5'        32'   
Y

Compacts:

* Bausch & Lomb Custom Comp. 7x26  1       1       2         6'      27.5'   
Y
  Leica 10x25 BCA                  3       4       3        16'        20'   
N
  Leica 8x20 BCA                   3       4       4         8'      26.3'   
N
  Minolta Pocket 7x21              2       4       5         6'      26.3'   
N
  Minolta Compact 8x23             2       3       5        21'        25'   
Y
  Nikon Travelite III 9x25         2       2       3        12'        20'   
Y
  Pentax UCF 8x24                  3       2       5       8.5'        25'   
N
  Redfield 8x24                    2       4       5      14.5'      28.5'   
N
  Swift Micron 8x25 CF             2       3       4         6'        20'   
Y
  Zeiss Design Selection 8x20 BT   2       3       4         8'        25'   
Y

* Top rated        Numeric Ratings: 1 to 5, 1 is best

4.3. British Birds (Owner Survey, Binoculars and Scopes, July 1991)
==================================================================

From _British Birds_, 84:7, July '91, pp. 267-282. Thanks Adrian Wander.
 
Most Popular Binoculars
-----------------------
1  Zeiss West Dialyt 10*40       28.4%
2  Zeiss West 7*42                8.8%
3  Leitz Trinovid 10*40           6.0%    Other well known makes placed:
4  Swift Audubon 8.5*44           5.5% 
5  Optolyth Alpin 10*40           4.9%    11 Bausch and Lomb Elites 10*42 
1.7%
6  Optolyth Alpin 10*50           4.2%    12 Bausch and Lomb Elites 8*42  
1.4%
7  Zeiss Jena Jenoptem 10*50      3.7%    13 Leica 10*42                  
1.3%
8  Leitz Trinovid 8*40            2.8%    16 Leitz Trinovid 7*42          
1.2%
9  Swarovski/Habicht Diana 10*40  2.4%    17 Zeiss West Dialyt 8*30       
1.1%
10 Zeiss Jena Notarem 10*40       1.9%
 
Most Highly Rated Binoculars
----------------------------
(6=excellent 5=very good 4=good 3=satisfactory 2=poor 1=very poor)
 
   Make                          No Owners  Average Rating
1  Bausch and Lomb Elite 8*42       12          6.00
2  Leica 10*42                      11          6.00
3  Optolyth 9*63                     5          6.00
4  Zeiss West 7*42                  72          5.94
5  Leitz Trinovid 8*40              23          5.87
6  Bausch and Lomb Elite 10*42      14          5.86
7  Leitz Trinovid 7*42              10          5.80
8  Leitz Trinovid 10*40             50          5.78
9  Zeiss West Dialyt 10*40         241          5.76
10 Leica 8*42                        4          5.75
 
(13 Zeiss West Dialyt 8*30           9          5.56
 14 Swarovski/Habicht Diana 10*40   20          5.50
 20 Zeiss West 10*50                 4          5.25
 21 Swift Audubon 8.5*44            46          5.20
 23 Optolyth Alpin 8*40             11          5.09)
 
Most Satisfactory Binoculars (number of owners who would buy the same again)
----------------------------------------------------------------------------
 
1  Leica 8*42                         4/4        100.0%
2  Bausch and Lomb Elite 8*42        11/12        91.7
3  Zeiss West 7*42                   61/73        83.6
4  Leica 10*42                        9/11        81.8
5  Bausch and Lomb Elite 10*42       11/14        78.6
6  Optolyth Alpin 8*30                2/3         66.7
7  Zeiss West Dialyt 10*40          154/236       65.3
8  Nikon 8*30                         4/7         57.1
9= Swarovoski/Habicht Diana 10*40    10/20        50.0
9= Opticron Classic 10*42             3/6         50.0
 
(14 Swift Audubon 8.5*44             15/46        32.6
 15 Optolyth Alpin 10*40             13/41        31.7
 16 Leitz Trinovid 7*42               3/10        30.0
 20 Optolyth Alpin 10*50              9/35        25.7
 21 Leitz Trinovid 10*40             12/50        24.0
 22 Leitz Trinovid 8*40               5/23        21.7
 24 Optolyth Alpin 8*40               2/11        18.2
 26 Zeiss West Dialyt 8*30            1/9         11.1)
 
Top Binoculars for the Future (intended future purchases)
---------------------------------------------------------
 
1  Zeiss West Dialyt 10*40        28.5%
2  Zeiss West 7*42                13.8%
3  Leica 10*42                     8.8%    Other well known makes placed:
4  Leica 8*42                      4.2%
5= Leitz Trinovid 10*40            2.8%    11 Optolyth Alpin 10*50     1.8%
5= Swift Audubon 8.5*44            2.8%    14 Leitz Trinovid 8*40      0.8%
7= Bausch and Lomb Elites 10*42    2.6%    16 Swift Audubon 7*35       0.7%
7= Bausch and Lomb Elites 8*42     2.6%    18 Zeiss West Dialyt 8*30   0.5%
9  Optolyth Alpin 10*40            2.3%
10 Swarovski/Habicht Diana 10*40   1.9%
 
Most Popular Scopes
-------------------
 
1  Kowa TSN1/2 *77                              16.2%
2  Bushnell Spacemaster *60                     12.2%
3  Kowa TSN3/4 *77                               7.7%
4  Optolyth TBS/G80                              7.5%
5  Optolyth 30*75                                6.9%
6  Nikon Fieldscope EDII *60                     5.8%
7  Kowa TS1/2 *60                                4.7%
8  Nikon Fieldscope ED *60                       4.5%
9  Opticron High Resolution *60                  3.6%
10 Bushnell/Bausch and Lomb Discoverer 15-60*60  3.2%
(11  Optolyth 30*80                              2.1%
 12= Questar Mirrorlens                          1.9%)
 
Most Highly Rated Scopes
------------------------
(6=excellent 5=very good 4=good 3=satisfactory 2=poor 1=very poor)
 
   Make                          No Owners  Average Rating
1  Questar Mirrorlens              15            6.00
2  Kowa TSN3/4 *77                 59            5.93
3  Nikon Fieldscope EDII           40            5.90
4  Nikon Fieldscope EDI            36            5.89
5  Nikon Fieldscope I and II        7            5.71
6  Optolyth TBS/G80                62            5.56
7  Kowa TSN1/2 *77                125            5.46
8  Optolyth 30*80                  16            5.38
9  Adlerscope 25*80                 3            5.33
9= Swarovski/Habicht 30*75          3            5.33
(11 Optolyth 30*75                 52            5.17
 13=Kowa TSN1/2                    36            5.00
 15 Bushnell Spacemaster *60       94            4.86
 18 Bushnell/Bausch and Lomb
    Discoverer 15-60*60            25            4.52)
 
Most Satisfactory Scopes (number of owners who would buy the same again)
------------------------------------------------------------------------
 
1   Kowa TSN3/4 *77                47/59            79.7%
2   Nikon Fieldscope EDI and II    58/76            76.3%
3   Questar Mirrorlens             11/15            73.3%
4   Optolyth TBS/G80               31/62            50.0%
5   Nikon Fieldscope I and II *60   3/7             42.9%
6   Optolyth 30*80                  6/16            37.5%
7   Adlerscope 25*80                1/3             33.3%
8   Kowa TSN1/2 *77                37/125           29.6%
9   Optolyth 30*75                 13/53            24.5%
10  Bushnell Spacemaster *60       19/94            20.2%
(14 Kowa TSN1/2 *60                 4/36            11.1%
 16 Bushnell/B&L Discov. 15-60*60   1/25             4.0%)
 
Top Telescopes for the Future (intended future purchases)
---------------------------------------------------------
 
1  Kowa TSN3/4 *77                     20.5%
2  Nikon Fieldscope EDI and II         19.3%
3  Optolyth TBS/G80                     9.2%
4  Kowa TSN1/2 *77                      8.8%
5  Questar Mirrorlens                   3.5%
6  Bushnell Spacemaster *60             3.2%
7  Kowa TS601/602 *60                   2.7%
8  Optolyth 30*75                       2.3%
9  Optolyth 30*80                       1.6%
10 Nikon Fieldscope I and II            0.9%

4.4 Living Bird Quarterly (Scopes -- Autumn 1990)
=================================================

This summarizes "Scanning for Optics II" from _The Living Bird
Quarterly_, Autumn '90, pp 12-15, Bonney and Forbes-Robertson.  Highest
rating is 1, lowest is 5.

1. Kowa TSN-4 and TSN-2: winners; zoom clear; if you have the money, buy the
4.

1. Nikon ED II Fieldscope: excellent; smaller, lighter than Kowas; zoom clear;
   focus ring awkward; depth of field shallow.

2. Optolyth TBG80: very good; image not sharp at high power; smaller field-
   of-view than Kowa; shallower depth of field.

2. Mirador SSD: can't match TSN-2; good clarity, but dark.

2. Bausch & Lomb Elite 22x: not as clear as some; outstanding for eyeglasses.

3. Questar Field Model: phenomenal image; 6x, 50x, and 80x impractical for
   most birding; heavy. 

3. Celestron C-90: heavy; bright, clear image; small field-of-view; 33x only;
   focus awkward.

   [additional owner comments: also available is a 25mm orthoscopic eyepiece
   that yields closer to 40x; slow motion head available; Barlow lens
   accessory doubles power while retaining eye relief for glasses wearers;
   comes in stout camera case.]

3. Zeiss 30x60 B/GA: image bright, but mediocre; not up to Zeiss reputation.

3. Bausch & Lomb Elite 15-45x: only good, unlike 22x; image worse as zoom
   increases.

3. Bushnell Spacemaster: best inexpensive scope; use 22x, zoom not good.

4. Optolyth 22-60x 70mm: image excellent; field-of-view tiny; shakes in wind.

4. Swarovski 25-40x 75 NZ and 30-75x 75 NZ: didn't care for either.

4. Celestron C-60: disappointment; dark and moderately clear.

5. Meade Pathfinder II and Swift Searcher: bad image.


5. Sources for Optical Equipment
================================

If you belong to a buying service, try that first.  One example:  B & L
Elite 22 x 60 scope, list: US$750, best mailorder: US$400, buying
service: US$200.  Several credit cards offer buying services. Another
buying service that is somewhat widespread throughout the US is United
Consumers Club.

Also, check the New York City mail order sources that advertise in the
back of Popular/Modern Photography.  Be aware, however, that these places
often carry what are known as foreign market or grey market goods.  These
are products produced for sale in countries other than the US. Sometimes
these products are manufactured to different specifications; sometimes
they are identical. In any case, you will not have any US warranty on
the goods and may not get any frills either (carrying case, strap, etc.).
The prices are appealing, but caveat emptor.

Mail order purchases from New York discounters can be practical from
outside the US. Many Australasian netters have successfully ordered from
B & H. You typically pay about US$50 extra for insurance and express
mail.  Even with the extra costs, your price may be considerably less
than the best locally available discount price. In Australasia, this is
typically about 2/3 of the best local price, assuming you pay import
duty (in Australia) or GST (in New Zealand). These taxes appear to be
random; you may not be charged.  If you travel overseas and can purchase
duty-free, then the price difference is much smaller, and you may want
to deal locally for the convenience of service and repair.  With your
order comes an international guarantee, but you must ship your purchase
to your local distributor in the event that you need to use it.

Before buying any mail order optics, you should read the Mail Order Survey
that Douglas Blondin (blondin@blanca.att.com) maintains.  He posts this
survey, listing experience with most of national photographic and optics
stores, about once a month on rec.photo and rec.video.
 
The sci.astro newsgroup is a good place to ask about optics suppliers.
On this group, you will also find the Purchasing Amateur Telescopes FAQ
that Ronnie B. Kon (ronnie@cisco.com) maintains.

Birders often sell optical equipment as they upgrade to newer models.
Generally every issue of _Winging It_, the newsletter of the American
Birding Association, has offers of used equipment.

Suppliers
=========

ABA Sales (Colorado Springs, CO) 800-634-7736, 719-578-0607 -- This is the
sales organization of the American Birding Association.  They do a great
job of stocking items for birders.  Their optics selection is good and
their prices are becoming more competitive.  You cannot ask for better
service.  ABA members get discounts.  The catalog has a lot of useful
comparisons of optical equipment.

Birding (Amsterdam, NY) 518-842-0863 -- APPARENTLY OUT OF BUSINESS 

B & H (New York, NY) 800-221-5662, 212-807-7474 -- "I have bought tons
from B&H...highly approved of by the pros who haunt rec.photo.... They're
honest, don't bait and switch, add garbage pieces, tell you how much
everything including shipping will cost, when you'll get it, etc....
Their prices run slightly higher than some other NY mail-order houses but
honesty and fairness make it worthwhile."

Christopher's Ltd (Norman OK) 800-356-6603 -- "primarily an
astronomy-oriented optical dealer, but good selection, decent prices,
and top-notch advice on many spotting scope options." Their prices are a
bit higher than some, but they offer a 30 day return policy (subject to
a 15% restocking fee). They have a catalog with much useful information
about birding optics, including recommendations about which spotting
scopes work best as telephoto lenses.

City Camera (Dearborn, MI) 800-359-5085, 313-846-3922 -- They have a
birder on staff, and have a helpful flyer and specification.

Eagle 608-271-4751 -- "really helpful"

Executive Photo, (New York, NY) 800-223-7323, 212-947-5290 -- avoid, based
on many negative comments

| National Camera (MN) 800-624-8107, 612-546-6831 -- "helpful and
| straightforward; prices midway between Eagle or Christopher's and the NY
| camera stores; 30-day satisfaction guarantee; Kevin, the optics
| manager, was well-informed."

Orion (Santa Cruz, CA) 800-447-1001 -- large selection of interest to
birders. Prices are fairly high, and service varies depending on who you
talk to.

Yoder 216-893-2464

6. Useful Reference Material
============================

_Better View Desired_, Whole Life Systems, P.O. Box 162, Rehoboth, NM 87322.
Subscriptions are $15 per year (4 issues). A free sample issue will be sent
upon request. All back issues are available for $4 per issue: August 1992,
Mid-sized Binoculars; November 1992, High-powered Binoculars; February 1993,
Refractor Spotting Scopes; April 1993, Budget Binoculars; August 1993,
Full-Sized 7 and 8x Birding Binoculars; November 1993, Catadioptric Scopes;
February 1994: Compact Binoculars.

Culver and Gerhart, "Binocular Quest", _Living Bird_, Autumn 1992.

"Binocular and Scope User Survey", _British Birds_, 84:7, July 1991,
pp. 267-282.

Bonney and Forbes-Robertson, "Scanning for Optics II", _The Living Bird
Quarterly_, Autumn 1990, pp 12-15.

_Birding_ (photo issue), February, 1989.  See also the "Tools of the Trade"
column in most issues.

7. Contributors
===============

Thanks to the following individuals who have helped with this FAQ:

Bob Atkins, Don Baccus, David Braddon-Mitchell, Mike Burger, Byron
Butler, Dalcio Dacol, Richard Ditch, Derk Drukker, Mark Eckenwiler, Al
Eisner, Dave Eshbaugh, Annika Forsten, Jay Freeman, L. Gorbet, David
Graham, Burton Guttman, Sid Johnson, Frank Kolwicz, Tony Lang, Laurie
Larson, Tom Lathrop, Harry Lehto, Kevin McGowan, Peter Nurkse, David
Rintoul, Rocky Rothrock, Daan Sandee, Sandy Santra, Frank Suits, Brian
Townes, Tim Walker, Adrian Wander, Steve Willner, David Wright

[I apologize to anyone I have inadvertently left out -- let me know.]
--
Ed Matthews                                         Internet: edm@aib.com
AIB Software                                        Voice: (703) 430-9247
46030 Manekin Plaza                                   Fax: (703) 450-4560
Dulles, Virginia 20166-6518 USA
-- 
Ed Matthews                                         Internet: edm@aib.com
AIB Software                                        Voice: (703) 430-9247
46030 Manekin Plaza                                   Fax: (703) 450-4560
Dulles, Virginia 20166-6518 USA

