Fold-Down Eyeguards, Waterproof Binoculars

Since everyone’s eyes focus images slightly differently, different observers will need to refocus the binoculars for their own vision.

Fold-Down Eyeguards

BT70 binoculars feature fold-down eyeguards on the eyepieces. The eyeguards are usually left in the up position for use without eyeglasses, as this helps prevent glare from entering between your eye and the eyepieces. To use the binoculars with eyeglasses, you will need to fold the eyeguards down in order to get your eyes close enough to the eyepieces to see the entire field of view.

Waterproof Binoculars

The BT70 is nitrogen-purged and sealed to be waterproof and internally fogproof. While it is impervious to rain, wind, splashing, and humidity, do not immerse the binocular in water under any circumstances. If the binocular becomes wet with fresh water, merely blot it dry with a clean cloth and clean the lens surfaces as outlined below. Saltwater should be rinsed off completely and the binocular then blotted dry and its lenses cleaned as outlined below. If the binocular body becomes dirty, it can be cleaned with warm water and a clean cloth. If extremely dirty, or oily, clean the body with a dilute solution of warm water and mild soap on a cloth, then rinse with clean water and blot dry. Do not clean lens surfaces with soap and water!

Cleaning and Care of Binocular Lenses

The lens surfaces of Orion binoculars are coated with anti- reflection multi-coatings that can be damaged with careless handling. Avoid touching lens surfaces with fingers or any coarse material. All optics, even if stored, should be cleaned at least once a year or whenever they are dirty. The dust that builds up on coatings promotes mold growth, which etches glass and destroys coatings. Avoid over-cleaning; it can also damage the coatings. Always use lens cleaning tissue and fluid that are specifically designed for multicoated lenses. Do not use fluids or tissues that are for eyeglasses or household use. Never attempt to disassemble the binocular or eyepieces in order to clean them; this can also void the warranty.

To clean the binocular (and eyepiece) lenses, first blow off the lens with a blower bulb or gently wipe the lens with a lens cleaning brush to remove the larger particles. Put a few drops of lens cleaning fluid on a fresh piece of lens cleaning tissue (never on the lens) and gently wipe the lens. Quickly wipe the excess fluid with a new, dry piece of lens cleaning tissue. For larger lenses, clean only a small area at a time, using a new tissue each time. On excessively dirty lenses, wipe across the lens using one stroke for each tissue, alternating wet and dry. Always avoid excessive pressure or rubbing when wiping, as wiping too hard can scratch the lens.

Storage and Transport

The BT70 binoculars come with a heavy-duty case for safe storage and transport. We recommend always keeping the

binoculars in their case with the cover caps on when not in use. The case has a lock on each latch for extra security. Use one of the supplied keys to lock and unlock the latches. A removable shoulder strap is also provided for ease of transport.

Avoid unnecessary shocks to the binocular, whether it is in its case or not. Although the BT70 is designed to be mechanically rugged, excessive impacts may cause the optics to become misaligned. This is not covered by the warranty.

A metal carry handle is supplied with the BT70. This connects to the dovetail holder on the binoculars, which is located just in front of the eyepieces (Figure 1). Slide the handle’s base into the dovetail holder, and secure it in place with the thumbscrew. The handle comes in quite handy when attempting to mount the BT70 onto a tripod. Before the BT70 can be placed into its case, the handle must be removed.

Allow the optics to slowly adjust to cold weather by storing the instrument (in its case) in a cold area, such as an unheated garage or the trunk of a car, for a few hours before use. When bringing the instrument back inside a warm house, open up the case, remove the binoculars, remove the cover caps, and let everything dry out. The binoculars should be stored in a cool, dry place to prevent mold growth, which can damage the optics. This is not covered by the warranty.