Numbers - They Do Matter
Any hunting binoculars review should begin with a basic explanation of what numbers like 8 X 25 mean to the optics of those binoculars. The number on the left is the magnification made possible by the optics of the binoculars. So, an 8 on the left is how many times the binoculars magnify that bird you are looking at through the optical system. The number on the right is known in the optical world as the objective lens diameter. Basically, this is the size of your lens and it is measured in millimeters and it is very important to your optics. In the world of the hunting binocular, the larger the objective diameter, the better – the same also happens to be true for the binoculars used for birding as well.
The reason you want to go hunting for birds or other game with a pair of binoculars that have a larger objective diameter is because they can be used in low-light conditions such as dusk or dawn—times when most bird hunting occurs and necessary to take into account when designing an optics system. The larger the lens, the brighter the bird will be in the optical system. Now some compact binoculars do have a specialized coating on the lens which enhances the optics and actually helps capture more sunlight. But, all things being equal, the hunter will want to go with a larger lens and the enhanced optics that go with it to see birds and other game as clearly as possible.
Binocular Review by Joe "Woods Goods and Stuff"
