There are a few things that make binoculars better, but the number one reason is the precision of the grinding of the glass. Its just physics of how the glass bends the light and moves the focal point from a converging lense to your eye. The better the glass, the less distortion, the sharper the image.

Better binoculars will be filled with nitrogen which is an inert gas (will not react) to help prevent fogging of the internal parts of the lenses.

Lens coatings - good bincoulars have special coatings to help filter light and make images sharper. The more lenses that are coated, the more expensive the binocular.

Finally, the very best binos are usually waterproof down to a few meters.


You can get very good glass that is not waterproof reasonably priced. When you get into waterproof binos you get expensive.