For over 60 years, Bushnell has led the optics market. Binoculars, also known as field glasses, are basically two telescopes built together to provide the user two views of the same object, one from each eye. This gives Bushnell binoculars a depth perception and a clearer, cleaner image than would be possible with a telescope.What do the numbers on Bushnell field glasses mean?
Let’s use the Bushnell 10x50 Engage as an example. The first number, 10, is the magnification. A magnification of 10x (ten power) means a faraway object appears 10 times closer with field glasses than without them. The second number, 50, is the diameter of the objective in millimeters. The higher the number, the brighter the image.What is the field-of-view?
The field-of-view is the size of the area you are able to see at a distance when using Bushnell field glasses. If your binoculars specifications list "FOV = 393 feet at 1000 yards," it means that when you are looking at an object 1000 yards away, you can see an area of 393 feet.Which Bushnell binoculars are waterproof?
All Bushnell optics are purged with either nitrogen or argon and then sealed with O-rings to make them 100% waterproof and fogproof. During testing, every model of Bushnell optics is submerged for hours under both hot and cold water.What are the differences between Roof prisms and Porro prisms?
The vintage Porro prism has a bulkier, zig-zag design that resembles the letter Z. This means the barrels, and therefore the binoculars, must be bulkier to accommodate the Z. Roof prisms are lighter and more complex. Roof prism binoculars tend to be smaller, too.What is a diopter adjustment?
The diopter adjustment is the control knob that adjusts only one eyepiece on Bushnell glasses. It lets you adjust for the difference in vision between your eyes. Once the diopter is set to your needs, you can adjust the magnification by simply turning the central knob.How does one adjust the focus for one’s eyes?
To fine-tune the binoculars to your individual eyesight, do the following:
- Move the two sides towards, or away from, each other until you see only one image.
- Set the "diopter" -- single eyepiece adjustment, usually on the right side -- to zero.
- Using your hand or a lens cover, block the front glass on the side with the diopter adjustment.
- Using the focus adjustment, focus on a distant object until it becomes clear to the viewing eye.
- Cover the front glass on the side without the diopter adjustment.
- Look at the same object at the same distance as before.
- Adjust the diopter ring until you see the object clearly.
- For future reference, make a note of the diopter ring setting.