Galileo binoculars are produced to the highest standards for the ultimate in usability, durability, and image quality. Every binocular made by Galileo is built to stand the test of time and is backed by a limited lifetime warranty. Additionally all Galileo binoculars feature a full range center focus, carrying case, straps, armoring and a lens cloth.
If you have any question regarding the specifications or quality of Galileo binoculars do not hesitate to contact us.
Wide Angle Binoculars have a much wider field of view than binoculars of comparable power and objective lens size. For instance the Galileo DM-1025WP is a Wide Angle Binocular with a field of view of 342 ft. Where as the Galileo G-1025PC is not a wide angle binocular and field of view is 262 ft. Please scroll down for more information on Field of View.
Every binocular is composed of two optical systems paired together; one for the left eye and one for the right. Each of these contains two prisms which are position in one of two designs: Roof or Porro.
Roof prisms are positioned very close together, so close that the ocular or eyepiece is positioned directly behind the objective lens. As a result a roof prism binocular is more compact and generally more durable than anequivalent porro prism binocular.
Porro Prisms are positioned in such a way that the oculars or eyepieces are offset from the objective lenses (ie the objective lenses are much farther apart than the oculars). This makes the binocular bulkier but also affords them better depth perception than the roof prism design
The optical quality of the prisms in a binocular are a major factor in the quality level of the images produced by the binocular. The majority of todays binocular prisms are made from borosilicate prisms (BK-7) or barium crown prisms (BAK-4). BAK-4 prisms are a much higher quality prism than BK-7. BAK-4 prisms produce much brighter images and sharper images towards the outside edges than the lower quality BK-7 prism.
The optical parts of a binocular have different coatings applied to them. Below are the different coatings applied to binoculars and how they benefit the binocular.
Coated: A single layer of coating on at least one lens surface. Coated optics help to reduce glare.
Fully Coated: A single layer of coating on all air-to-glass surfaces. Fully Coated optics have improved glare reduction over coated optics.
Multi-Coated: Multiple layers of coating on at least one lens surface. Multi-Coated optics help to reduces glare and increase contrast & clarity
Fully Multi-Coated: Multiple layers of coating on all air-to-glass surfaces. Fully Multi-Coated optics exhibit improved reduces glare and futher increased contrast & clarity
Phase Coated: Chemical coating applied to roof prisms, porro prisms do not benefit from this particular coating. Phase Coatings are the highest quality coatings maximizing glare reduction, optimized light transmission, and enhanced contrast & clarity.
Many Galileo Binoculars can be attached to a tripod, some cannot. When shopping for a Galileo binocular please look in the corresponding description. Any Galileo Binocular with a binocular tripod socket can be used with a tripod. Please also note that other than the Galileo GR-BC2 and GR-BC3, all Galileo binoculars with a tripod socket must be used in conjunction with a binocular tripod adapter.
In binoculars Eye Relief is defined as the distance between the human eye and the ocular or eyepiece of the binocular needed to comfortably view images. That distance in Long Eye Relief binoculars is greater than that of regular binoculars. This is especially helpful to eyeglass wearers enabling them to use the binoculars withour removing their eyeglasses.
Most Galileo binoculars are water resistant protecting them from being splashed. Water proof binoculars are nitrogen purged to be fully water proof protecting them when fully submerged.
Nitrogen purging renders a binocular water proof and fog proof. Nitrogen purged binoculars can be completely submerged in water without being damaged. It also guards against fogging in the interior of the binocular due to extreme enviromental changes in tempurature and humidity.
Binocular users can often experience neck fatigue when wearing binoculars around their neck for an extended period of time. This is especially evident when using a regular neck strap. Galileo's neoprene neck strap is much wider and padded to relieve neck fatigue. Tha Galileo binocular harness eliminates neck fatigue all together supporting the binocular with the shoulders and back and also helps to keep the binocular close at hand.
Binoculars are often referenced by two numbers with an “x” between them (ie 8x40). The first number is the power of the binocular and the second number is the objective lens size. In the example 8x40 the power of the binoculars would be 8x makeing objects appear 8 times closer than with the naked eye.
In any optical system whether it is a pair of binoculars or a telescope, the more light that is brought in, the brighter and clear the images will be. Light is brought into the system through the objective lens or aperture. So the larger the the objective lenses of a binocular, the brighter and clearer the images will be.
Many binoculars today boast having a zip focus or fast focus. This is accomplished by making the focusing range much shorter and therefore much more sensitive which makes acheiving a precise focus very difficult. As a result image quality is much lower not because of the optics, but because of the inablity to properly focus them image. All Galileo binoculars feature a full range focus for optimum image quality.
Field of view or FOV is defined as the distance one can see from left to right in a binocular. FOV is measured in one of two ways linear and angular. Linear is the most common form of measuring FOV and is measured at 1000 yards. For example the Galileo C-735WA has an FOV of 500 feet, meaning that when you look through the binocular you can see 500 feet from left to right at 1000 yards. Alternatively the angular FOV is a measurement of a binoculars FOV in degrees. In the example of the C-735WA the angular FOV is 9.5°
The minimum focus distance of a binocular is the closest you can be to an object and still be able to focus on it with the binocular.
The exit pupil is the diameter of the stream of light exiting the binocular. Generally the larger the exit pupil the brighter the image produced by the binocular. The word generally is used because if the exit pupil is 8mm is will not appear brighter than a binocular with an exit pupil of 7mm. This is because the human eye is not capable of dialating much larger than 7mm in which case the extra millimeter of light in an 8mm exit pupil goes to waist since it is not entering the eye. Also as the ambient light increases the pupils of the human eye constrict to cut out the excess light. So at mid day on a cloudless day binoculars with a large exit pupil are not as necessary as they are in low light conditions (ie from dusk till dawn).
It should also be noted that as a person ages their eyes gradually loose their ability to dialate. A young persons eyes can fully dialate to 7mm while a middle aged persons eyes can dialate to about 5mm and an elderly persons eyes to a maximum of about 4mm.
Eye Relief is defined as the distance between the human eye and the ocular or eyepiece of the binocular needed to comfortably view images.
Interpupillary distance is the distance between the human eyes or the distance between the oculars or eyepieces of a binocular. An IPD (interpupillary distance) scale is a small moving scale on the binocular usually near the center with a small notch that adjusts up and down the scale as you expand and contract the size of the binocular. An IPD scale can be useful when there are multiple people using the same binocular. It helps by helping a user remember what setting is most comfortable for them.
The Relative brightness index is a measurement of how bright a binocular will be given its power and objective lens size. It is calculated by dividing the size of the objective lenses by the power and finding the square of the resulting number. For example, the relative brightness index or RBI would be calculated like this (42/10)²=17.64. It is important to note this value in a binocular when brightness and clarity are important. While one might think that a 10x42 binocular is brighter than a 7x35 because it has larger objectives, the 7x35 would actually produce brighter clearer images. This fact can be seen when comparing the RBI values: 10x42⇒17.64 — 7x35⇒25.
The Twilight Factor is supposed to be a measurement of how much you can detail can be seen in low light conditions (or twilight hours) when the human eye has not had time to adjust. This measurement tends to favor magnification which many binocular makers use to sell their binoculars. It is for this reason that it is not suggested that a binocular be purchased based on its twilight factor. It is much better to have a higher Relative Brightness Index than it is a high Twilight factor. For those how find the twilight factor useful it is calculated by multiplying the power by the objective and then finding the square root.