Understanding Optics & Coatings
ED glass: The Pentax ED series bring about a remarkably sharp resolution and contrast-rich image thanks to their Extra-low Dispersion Glass or ED Glass for short. It is used in the finest optics and used by professionals who require the details in an image to be clear and bright. The ED Glass reduces ‘color-fringing’ thanks to its ability to keep differing wavelengths of light together which also increases the resolution of the image so that all details are bright, and color-accurate as in the image above.
Multi-Layer Lens Coatings: This basically means that the lenses have received multiple layers of anti-reflective coatings on all air-to-glass surfaces which increase light transmission to produce a brighter image and therefore better low light performance. Anti-reflective coatings can make a really big difference on the brightness of the image produced. It is not unusual to look through binoculars with smaller objective lenses, but with higher quality anti-reflection coatings and seen them outperform binoculars with much larger objective lenses, but with fewer or no coatings. The diagram above shows how these coatings improve the transmission of light.