Yelomin Zoom Monoculars Telescope,24X30 Dual Focus optics Multi-coated Lens BAK4 Prism Spotting Scope with Tripod and Cellphone Adapter Suitable for Bird Watching,Sport Games and Concerts (8X)

Product Hightlights- BAK4 Prism Design- Fully Multi-Coated Lenses- O-Ring Sealed/Waterproof & Dustproof- Nitrogen-Purged/Fogproof- Durable Rubber Armoring- Twist-UP Eyecup- 30mm Eye ReliefOptical Performance8X to 24X Magnification30mm objective lensFully Multi-CoatedHD Lens ElementsSpecificationsThere are several monocular specifications that are important when choosing one to buy. The first impulse of many people is to go big on magnification, but going for the greatest magnification is often not the best choice. You need to consider objective lens size and field of view, too. MagnificationWhen you're choosing a monocular, you'll see two numbers in the specs - for example, 8 X 30 or 24 X 30. The first number is the magnification. In these two examples, that means what you see is eight times normal size or twenty-four times normal size.Bear in mind that as magnification increases, the monocular gets bigger and heavier. It also becomes harder to hold the image steady. Our advice is to think about what you'll be viewing most often and choose your magnification accordingly.Field of viewIncreasing the magnification reduces field of view (FOV), the area you see when looking through the device. If you want to examine the individual feathers on a bird 1,000 yards away, a wide FOV isn't important. If you want to scan an area for wildlife, FOV is important.There's no perfect answer as to FOV - it's a question of making the best compromise. Most manufacturers give FOV figures, usually stated as feet per 1,000 yards (240 feet/1,000 yards, for example).Objective lens sizeThe second number in the two examples above (8 x 30 and 24 x 30) is the objective lens size in millimeters. The larger this number, the more light gets into the monocular, and the clearer the view.