With the ZEISS 10x40 SFL binoculars (SmartFocus Lightweight), special moments can be experienced with ease. Optimized to be as lightweight and compact as possible, the SFL binoculars are a perfect addition to the SF family. The new Ultra-High-Definition (UHD) Concept ensures true-to-life color reproduction and the highest level of detail. Thanks to its SmartFocus Concept, the focus wheel is perfectly positioned and enables fast and precise focusing – even with gloves on. The optimized ergonomics and a large exit pupil allow for a relaxed and undisturbed viewing experience.
With a field of view of up to 115 meters at a distance of 1,000 meters and a closest focusing distance of 1.5 meters, the SFL 10x40 deliver a perfect overview combined with precise detail recognition.
The lens diameter has been reduced by 2 mm, making it possible to use thinner lens elements at closer spacing and thus reduce the binoculars’ weight by up to 20% and their volume by up to 13% compared to the ZEISS Victory SF models. As a result, the SFL binoculars are up to 30% lighter than comparable products from competitors.
Experience nature in all its splendor
The Ultra-High-Definition (UHD) concept features a special coating and an improved optical design that ensures the binoculars deliver the highest level of detail and reproduce colors with natural fidelity. This makes it possible to precisely identify the smallest features in the plumage and reliably distinguish between species.
SmartFocus Concept for an intuitive and precise handling
The SmartFocus concept makes it possible to focus quickly and precisely – without having to spread your fingers. The focusing wheel, perfectly positioned in the DoubleLink Bridge, offers the highest level of operating ergonomics, requiring only 1.4 turns from close focus to infinity and capable of being rotated precisely even with gloves on.
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90% Light Transmission
Featuring 90% light transmission and ZEISS T* multicoating, you can clearly and precisely recognize details in the twilight, ensuring that you capture every moment, even in darker environments.
Comfortable viewing experience
The perfect ergonomics of the ZEISS SFL models enable quick and easy positioning of the eye and also provide comfortable and immersive viewing due to the large exit pupil. In addition, the improved eyecups provide an even better ergonomic feel and a smooth transition between the touch points, which are precisely defined and can be reached perfectly.
ZEISS T* Coating
ZEISS T* coating is a guarantee of the brilliant, high-contrast images which you will experience above all in adverse light conditions and in the twilight. Behind it, however, there is no specific formula for building up the layers. Instead, it is a technology that is constantly adjusted to suit new glass materials and requirements, which varies from lens to lens.
A clear view, whatever the weather
There are always exciting things to be seen in the world of nature – even in wet weather. This is why ZEISS developed LotuTec®. A coating for the lenses of binoculars and spotting scopes that enables a clear and unhindered view in all weather conditions.
Performance
| Magnification | 10 × |
| Effective lens diameter | 40 mm |
| Light transmission | 90% |
| Exit pupil diameter | 4.0 mm |
| Twilight factor | 20.0 |
| Field of view at 1,000 m (yds) | 115 m (345 ft) |
| Subjective viewing angle | 62° Ww |
| Close focusing distance | 1.5 m (4.9 ft) |
| Diopter adjustment range | − 4.0 | + 4.0 dpt |
| Exit pupil distance | 18 mm |
| Pupil distance | 52 – 74 mm |
| Lens type | UHD |
| Prism system | Schmidt-Pechan |
Features
| LotuTec | Nitrogen filled | + | + |
| Water resistance | 400 mbar |
Physical
| Operating temperature | − 20°C | + 55°C (− 4°F | + 131°F) |
| Length | 144 mm (5.7 ") |
| Width at an interpupillary distance of 65 mm | 114 mm (4.5 ") |
| Weight | 640 g (22.6 oz) |