About telescopes. Characteristics of low-light night vision

In fact, all telescopes have the so-called "low-light night vision" function.

Telescopes not only bring images closer, but also have an important parameter, that is, the ability to amplify brightness. Also known as "light gathering ability".

The formula for calculating the condensing force is: the square of the telescope aperture (mm)/ the square of the maximum pupil diameter of the human eye, and the maximum pupil diameter of the human eye is 7 mm.. It can be calculated as: the square of the aperture /49. Your telescope aperture is 50mm, and its concentrating power is 50X50/49, which is about 5 1 times.

So when you observe the target with this mirror at night, not only the distance of the target is 10 times closer, but also the light source is enlarged by 5 1 times.

In this way, even if there is a small bright spot in the distance, it will be very bright when viewed through a telescope.

This is what merchants call "low-light night vision", so I say that all telescopes have "low-light night vision" function.

The real low-light-level night vision function is not available in general telescopes. There is a kind of "low-light night vision device" that has the real low-light night vision function, but the price is not several thousand, but it may be tens of thousands.