There are two kinds of prism designs in binoculars. One is the Porro prism. This is the tradition binocular shape with a hump design. This style is often cheaper to buy because it is more economical to manufacture. For the best image quality and brightness, Bak-4 prisms are a very good Porro prism style of binoculars. Many people prefer a roof prism design rather than a Porro prism. Roof prism style binoculars are easier to seal and make waterproof. They are sleeker. The PC roof prism gives sharper images than those of the regular roof prism. Roof prism binoculars are more streamlined and are often more durable than the Porro prism type.The Best Way to Compare Binoculars:

Look through the binoculars to see how close you can focus them.Do the colors project correctly through them?Are the binoculars Porro prism or roof prism design?Check the imagine quality, both at the periphery of the image and at the subject midpoint.Check the weight - how long could you comfortable use and carry the binoculars?If you are seeking binoculars for marine use, birding, hunting or other outdoor pursuits, consider waterproof or water resistant binoculars.If you wear spectacles, look for a pair of binoculars that will be comfortable and also give you a clear, sharp picture.Do the binoculars come with a protective case, well-fitting lens covers and a comfortable neck strap?Whether you are thinking about sporting optic binoculars, spotting scopes, monoculars or night vision goggles, all of these use the same nomenclature which shows the feature of any optic lens. For example, if you have a 10x42mm pair of binoculars, the numbers tell you the variable magnification specifics. The 10 is the power of the binoculars. This means the object you are looking at through them will look 10 times closer than when compared to the naked eye. The 42mm means the objective lens diameter. These are the optics on the end of the binoculars.

The size of the optic lens determines how much light enters the binoculars, in the same way that a camera aperture lens works. If you plan to use your binoculars for low light situations, such as astronomy or hunting, large objective lenses are important. You should also consider your field of view when buying the binoculars.A field of view of 390o for example would mean the width of whatever you are looking at is 390 feet at a distance of 1000 yards. All of this is decided by the magnification of the binoculars, the focal lengths of the eyepieces and the objective optical lenses. The higher the magnification, the less the field of view.The transmission of light through your binoculars depends on how much light there is able to pass through them. An anti-reflective coating on the optic lens of your binoculars can be useful because it increases the amount of light that will reach your eyes. The more multi-coatings there are, the brighter and sharper your images will be. A rain-resistant coating will decrease rain droplets, resulting in lessened light reflection.

This is ideal if you plan to use your pair of binoculars for bird watching, hunting, maritime activities or any other outdoor hobby. Your lenses should be protected when not in use, by making sure you always replace the lens covers when you are not looking through the binoculars. This is a good habit to adopt.Owning your own pair of binoculars means you can choose the perfect pair to suit the activities you want them for. Also, you will never miss the action because of being too far away. You can enjoy bird watching, boating, hunting, and sporting events all the more if your binoculars are comfortable for you and of good quality.You can even take photos with a pair of digital camera binoculars. Whether you are looking for astronomy binoculars, birding binoculars, night vision binoculars or another kind, make sure you spend adequate time trying out various pairs of binoculars to see which are the best for you and do not rush your choice.

Source: Big Porro Binoculars, Compact Porro Binoculars