What about the multiple of the telescope?

Representation method of fixed magnification telescope: magnification x objective aperture (diameter, mm), for example, 7×35 means that the magnification of this telescope is 7 times and the objective aperture is 35mm；; 10 x 50 means that the magnification of this telescope is 10, and the aperture of the objective lens is 50 mm

The magnification of a telescope refers to the magnification of the telescope, which refers to the magnifying power of the telescope to objects. For example, if you observe an object with a 7-fold telescope, the effect observed by an object 700 meters away is similar to that observed by the naked eye 100 meters away.

The exit pupil diameter is a very important parameter, but it is often ignored. In fact, the diameter of the exit pupil is the maximum aperture of the camera lens, which determines the brightness of the telescope image field.

Extended data

The aperture of the telescope objective is expressed in millimeters, and the magnification is a number. If a telescope is marked with the words 10*50, it means that its objective aperture is 50 mm and the magnification is 10.

A mistake in buying binoculars is that the bigger the multiple, the better. Actually, it is not. The larger the multiple, the smaller the field of view of the telescope and the more targets to look for. Moreover, when holding a telescope, the greater the magnification, the greater the influence of arm and body jitter.

The larger the aperture, the better the optical performance of the telescope, but the price and weight of the telescope also rise linearly. The caliber below 30 mm is called small caliber, 30 mm to 50 mm is called medium caliber, and above 50 mm is called large caliber.

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