Zeiss SFL 10x50 BinocularsZeiss SFL 10x50 Binoculars feature magnesium alloy chassis and thinner lens elements resulting in being up to 15% lighter than other 50mm binoculars. The SFL 10x50 weighs 30. 8 ounces. All 50mm SFLs have a 5. 9' close focus. The SFL 10x50 has a 366' field of view at 1000 yards. Combining their 50mm objectives with 90% light transmission results in bright images, even in low light situations. A 50mm objective lens collects 42% more light than a 42mm