Eyeskey 10x50 binoculars with expensive ED glass lenses

Premium binoculars with the highest quality ED glass lenses ED stands for Extra Low Dispersion This allows lens manufacturers to exploit the difference in refractive index between different lens elements to help reduce color cast more effectively and reduce side effects. Different types of glass have different refractive indices: different amounts of light that bends when it hits the glass. When light of different colors hits the glass, the different colors bend by different amounts. When the resulting image has different colors that do not align properly, this is called chromatic aberration or "color fringing". A lens has many different lens elements: some where light enters or leaves a convex surface, and others where light enters or exits a concave surface. At each step, the different colors will become more diffuse or closer together depending on the orientation of the lens surface. It is possible to "fix" color fringing to some extent by adding more lens elements that reverse the color separation effect of previous lens elements. This is quite tricky because you don't want to change the other focus/zoom effects of the previous lens elements too much. A low dispersion element (like ED) can help a lot with this, because then you can use the difference in refractive index between different lens elements to achieve an effect that you could not otherwise use ED lenses only in the highest quality optics. Magnification 10x Objectives diameter - 50mm Tripod thread - yes Antireflection coating on all lenses and surfaces Phase coating on prisms - on all surfaces Water resistance - full, up to 2 meters immersion in water for 30 minutes Nitrogen filling - nitrogen filled corrections - available Focusing - central Price - CHEAPER than on Aliexpress. Just look at the price with ED glass, ordinary binoculars are much cheaper. This binocular meets the most stringent modern requirements and gives a clear and juicy image throughout the entire field of view. Color reproduction is perfect, and due to the use of premium ED glass, chromatic aberrations are reduced to the limit. In all respects, these binoculars match the top binoculars of well-known brands (Nikon, Canon, Olympus, etc.) with a price of up to 600 US dollars. Recently came the buyer "with ambitions." As it turned out, knowledge in the field of optics is slightly more than zero. He compared 7x42 binoculars and hoped that 10x50 would be brighter! Therefore, for such buyers, before trying to look cool, I recommend at least a little Google on the part of binoculars and optics as such. 7x42 binoculars have an exit pupil with a diameter of 42 / 7 = 6mm, 10x50 binoculars have an exit pupil with a diameter of 50 / 10 = 5mm. Obviously, other things being equal, 7x42 binoculars will be brighter. Do not confuse exit pupil diameter with