Traditional Culture Encyclopedia - Photography and portraiture - What aperture does t 1.5 equal?

What aperture does t 1.5 equal?

The aperture of 1.5, in fact, the value of t is also the aperture, and the value of t is approximately equal to the value of f, both of which represent the aperture. It can be said that the value of t is an accurate value obtained by accurate measurement, while the value of f is calculated by a formula, and F= lens focal length/lens effective aperture diameter, which is the value of f obtained by this formula. However, it should be noted that the value of T and the value of F are likely to be very different. Through accurate measurement, all the influencing factors are taken into account. The value of T is the value of combining shutter and sensitivity when we take pictures.

F value, which does not include other factors, such as lens and coating. , will affect the actual luminous flux. It is very likely that the lens with large aperture, such as 50 1.8 lens, has a t value of 2. 1, 2.2. Because when we take pictures, the error tolerance rate of the pictures is very high, so this difference has little influence on the pictures. However, everyone watches movies, and friends who know about film and television photography should know that the focal plane is generally marked with t value. Because the film's fault tolerance rate is limited, and in order not to destroy the picture atmosphere, it is represented by t value.

T value is the most accurate compared with F value, so you can know the quality of a shot by looking at T value. Leica 50 0.95 sold for more than 70,000 yuan, but its F value is the same as its T value, which is enough to know Leica's optical technology, and it is also expensive.