Premium Zeiss Optics in an Inexpensive form
- Renowned Schott ED glass for bright, sharp images combined with premium multi-layer coatings on all glass surfaces offering reduced chromatic aberration to create clearer, color-accurate images.
- Phase-Corrective and Multi-Layer prism coatings on a BaK-4 prism increase light transmission, brightness, contrast, and color fidelity
- Exceptional Field of View ranging 375ft. @ 1000 yds. rivaling other models in this range.
- Amazing Close-Focus at 5.3ft.
- Generous Eye-Relief at 18mm for eyeglass wearers so you never have to struggle to see your target through the lenses.
- Stiff, Adjustable Diopter, unlike some models where you can easily knock one barrel out of focus.
- Large, textured focus wheel for a great grip and a smooth resistance for accurate focusing. Only 1.5 turns to go from close-focus to infinity.
- A reliable rubber armored housing made of Magnesium offers low weight, and prevents damage from minor impacts.
In Depth Features
Schott ED glass:
The glass in the Terra ED’s is made with Extra-low Dispersion properties, commonly found in higher-end binoculars. This means that whenever light passes through glass, it gets prismatically dispersed because of the different light wavelengths bending at slightly different angles from each other. Extra-low dispersion glass contains heavy metal elements that help to keep these light wavelengths together. This means that you get less of the color fringing on the edges of brightly lit or high-contrast objects. We may not even see the fringing in certain situations, but we perceive such images as being more blurry, lacking the razor sharpness we like without ED glass.
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.
Compact, Ergonomic Form & More
The Terras have quite a compact frame, especially if you’re used to the tall feel of other Zeiss binoculars. The Terras measure just 5.9 inches tall with the eyecups fully extended (5.5 inches, folded down). The smaller frame corresponds to a lighter weight, as the 8x Terras weigh just 26.3 ounces with rainguard and lens caps on (24.6 ounces without the covers). The 10x model is slightly lighter at 26.1 ounces. The compact size and lighter weight make them very comfortable to carry and handle. The balance of weight in the Terras is just right, so they sit in the hands fairly comfortable. There’s not a lot of molding in the rubber armoring: no dramatic thumb grooves or flanges that fit against the webbing between forefinger and thumb. It’s just basic black rubber armoring with a ridge along the upper side of the barrels that falls naturally on your palm just where you bend your fingers. That does impart more comfort in the hand.