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The key to choosing binoculars and telescopes comes down to the ability to test in 'field' conditions, comparing like for like
products in an unhurried manner. If you cannot see further than a few hundred yards/metres, and/or find yourself looking at the inside of a shopping centre or high street it's unlikely you'll have made the
correct choice
Telescopes for birdwatching have become very popular. Once you've used one, you'll see why. They add an exciting
new dimension to birdwatching. Unlike binoculars, scopes can be purchased in sections - body, eyepiece, photoadaptor and usually with a suitable support such as a tripod. You need to take trouble over getting the
combination of parts right.
What magnification do I need?
Magnifications are available from as low as 15x or as high as 50x, or even higher with some specialist scopes. Some have a fixed
eyepiece, usually with magnification of 20x and a relatively wide field-of-view, but many have a range of interchangeable eyepieces to choose from. 20x to 30x wide angle are good for general use, and a 40x may be
useful for distance work, e.g. viewing raptors. At high magnifications you lose image brightness and field-of-view, you'll need a fixed support, and it's harder to focus precisely. Eyepieces of 60x and
above can only be used in bright light and on a fixed support (for viewing stationary birds). Bigger doesn't mean better! Variable focus or 'zoom' eyepieces work well with some scopes and usually cover
ranges of 15-45x or 20-60x. The most compact scopes have 60mm objective lenses, which are ideal for general viewing, less so if the light is poor. Using a 20x or 22x wide-angle eyepiece ensures that you get
maximum light-gathering. There are plenty of versions with larger objective lenses, usually between 75mm and 80mm diameter. These have increased low-light capability, but also increased size and weight. They are at
their best with a 'zoom' eyepiece, and with high-powered eyepieces of 40x or more you get better image brightness too. Wide-angle 20x or 30x eyepieces also do well on these models.
Basic guidelines
For field work, walking and general observation, try a compact 60mm scope with a 20x or 22x wide-angle eyepiece. For greater power choose
a 30x wide-angle or 40x. In low light, or when observing from a hide or any other fixed position, the larger 75/80mm scopes are ideal. You can fit fixed 20x, 25x or 30x eyepieces, or a 20-60x 'zoom'
eyepiece. 'Zoom' eyepieces are fine when you need a range of magnifications, but the field-of-view is less than fixed eyepieces at equivalent magnifications. If you wear glasses, you can get eyepieces
with a fold-back rubber cup: you can keep your glasses on, but remember that you may lose some field-of-view.
Straight or angled eyepiece?
Straight Easier to use and find birds at first. Easier to use with a shoulder-pod.
Best for hide use or viewing from a vehicle.
Angled Easier to watch birds in trees, or viewing downwards, e.g. seabirds from cliffs Useful if sketching or using a notebook.
Your tripod doesn't need to be so high, so it's more stable. More comfortable for long term observation.
The angle of the eyepiece doesn't affect the interchangeability of items such as
photoadaptors. The choice depends entirely on your personal preference.
Fluorite and ED (Extra Low Dispersion) Optics
Some products are available with ED, HDF or Fluorite glass optics. These are high-grade optical glass elements (used in objective lens
construction) offering enhanced image definition, higher contrast and more accurate colour. You can find them across the price range, but they are most effective in top-quality scopes specially designed to get the
best out of Fluorite and ED optics.
How to care for your equipment
Don't forget to insure your equipment on an 'all risks' basis.
Do NOT let your optical instruments get wet unless you're sure they're guaranteed waterproof. Don't let them suffer impacts or extremes of temperature. Don't over-clean the lenses this can
damage them, and often does. Just breathe lightly on the lens surface and wipe carefully with a micro-fibre cloth. Don't use lens cleaning fluids or impregnated cloths, which leave residues and cause smearing.
If your binoculars or telescope do get wet and moisture reaches the interior, let them dry out in a warm atmosphere and then take them to a specialist dealer for cleaning and servicing. On no account try to do
repairs yourself. Letting air into an already moist instrument just makes matters worse. If you're using your scope in the field, do NOT hang the tripod under the scope by using the scope's stay-on case
strap to carry the whole kit. This can prove to be an expensive mistake! Place a tripod strap round the tripod so that the scope sits on top of the outfit
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