I keep seeing 40×60, 12×50 and 10×50. What do they mean and what would be the better option for different applications?
In: Technology
The first number is the maximum magnification, how much bigger the object will appear to be. So the first telescope will make things 40x bigger, the second will make it 12x bigger, and the third will make it 10x bigger, at max zoom.
The second number is the diameter of the primary lens (or mirror) in millimetres, which describes how much light it is actually capturing. This will make objects such as the moon appear clearer. When it comes to viewing stars, the larger the lens, the dimmer stars you’ll be able to see, and you’ll be able to see more stars as two distinct objects when they would otherwise ‘blend’ into one.
Generally the telescope should say it’s intended use, but really the only benefits of telescopes with smaller numbers is they’re cheaper and lighter. A larger telescope will (assuming its manufacturered to the same standard) provide a better image.
Generally speaking, the larger telescopes will be reflectors, and these are typically meant for stargazing. Smaller telescopes are for casual/beginner use, obtaining a larger field of view when using a larger main telescope, or for terrestrial use (ie spying on your neighbors.
The first number is the magnification and the second is the objective size, the lenses farther from your face. Higher magnification reduces your field of view. Larger objective lenses can allow more light in. If you divide the objective size by the magnification, in the case of 8x42mm, 42/8 = 5.25mm, you get the exit pupil size. Having a higher exit pupil size can help you see better in low light environments.
The first number is the magnification…how much bigger it makes things look.
The second number is the size of the main lens, in mm. That measures how much light the binoculars are gathering, which helps with having both a bright and sharp image.
The second number will dominate the size/weight of the binoculars. If you want something that fits in your pocket you don’t want 100mm lenses. But if you want to see things at night you do want big lenses (more light).
The magnification all depends on what you want to look at…are you looking very far away at tiny things? Big magnification. Do you just want to look at ships a mile away? Maybe 10x is fine.
High magnification with small lenses will be dark and fuzzy. Low magnification with huge lenses is kind of overkill…it’ll look really good but it’s not really helping. You need a balance.
Binoculars are often specified by a set of numbers such as 7×35 or 8×40, the first number indicates the strength of magnification (how many times closer the subject is to you, 5 times closer, 7 times closer, 10 times closer) and the second number is the size of the objective lens measured in millimeters going across the lens. The size of the objective lens will determine how much light the binocular can obtain for effective viewing. The higher the number, the larger the lens; in effect allowing more light to pass through thereby projecting a brighter image and viewing experience. However, binoculars with smaller lenses are more compact and portable.
Latest Answers