Take pictures. What do they mean by positive and negative?

Positive film, also called negative film. It is the general name of photographic film used to print photos, slides and movie copies. The negative image on the negative can be printed as a positive image, so that the brightness or color of the image is the same as that of the subject. The sensitivity of black-and-white positive film is limited to purple-blue light, and the sensitivity of color positive film is weaker than that of color negative film, so positive film is rarely used in photography.

A negative is an image obtained after exposure and development. Its brightness is opposite to that of the main body, and its color is the complementary color of the main body. It needs to be printed on a photo to be restored to a positive film. The negative used to develop photos is negative. In black-and-white movies, people's hair is white on the negative, but in fact, white clothes are black on the negative.

Extended data:

colour positive film

Color positive is used to print color projection copies (movies, slides). Not for shooting, low sensitivity, full illumination type. Features are: large contrast, low haze, high clarity and low sensitivity (and slides and actual effects are mirror images).

Color film used for shooting, which forms a transparent positive image after exposure and development. One of the main uses of color reversal film is to make slides, and the other is to make plates by printing. Its image clarity, color saturation, gradation and granularity are better than color photos.

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