What is the basic knowledge of photography?

Photography has two meanings:

One refers to the film crew. Filmmakers are the embodiment of film plastic arts. A film-the fruit of all the creative workers' labor-was shot by a photographer one shot at a time. He "created" with the director, that is to say, as a photographer, his duty is to realize the director's creative intention and artistic conception through photography under the guidance of the director's creative thought.

The second is the process of shooting scene images with film cameras. Usually includes three steps:

Firstly, the shape of the scene is exposed on the photosensitive film through the lens to form a latent image;

Secondly, the exposed photographic film is treated by chemical processes such as development and fixing to obtain a negative image with brightness opposite to the scene or color complementary to the scene, that is, a negative film;

Finally, another photosensitive film is exposed through the negative, and then chemical treatments such as development and fixing are carried out to obtain a positive image with the same brightness or color as the shooting scene, that is, a transparent positive. There are also photos taken by using reverse photosensitive film, and transparent positive films are directly obtained through chemical treatment such as development and fixing.

Second, camera shooting

A camera has two meanings:

One is the cameraman. Photographers are the embodiment of plastic arts in TV teaching materials. Its duty is to realize the director's creative intention and artistic conception with camera means and skills under the guidance of the director's creative thought.

In addition, it also refers to the process of shooting landscape images with TV cameras.

Third, video recording.

Video has two meanings:

Refers to people who use video recorders.

The process of recording live images taken by TV cameras on video tapes with video recorders.

Fourth, exposure

The process of exposing photosensitive materials. The exposure depends on the illuminance and exposure time of the photosensitive material, that is, exposure = illuminance × time. The illuminance can be adjusted by the aperture size, and the exposure time can be controlled by the shutter speed. The film in a movie camera runs continuously at a constant speed. Generally, in addition to the aperture, the exposure is sometimes adjusted by the opening angle of the shutter installed on the fuselage.

1. exposure point

Obtaining the scene brightness control point with intermediate density on the film negative is also the reference point for exposure combination selection. In film production, its selection is restricted by the following interrelations: the brightness of the scene with intermediate reflectivity produces the intermediate density of the film, and the best visual effect of the screen is obtained by printing the film with standard light signals. In actual shooting, the specific lighting conditions of the subject are the main basis for selecting exposure points and measuring various parameters during exposure.

2. Underexposure and overexposure

The light in the shooting scene is dim, and the aperture is not adjusted properly when shooting, which leads to the dim picture. This situation is called "underexposure", and vice versa. Underexposure and overexposure are originally caused by photography errors, but sometimes they are deliberately underexposed or overexposed in order to obtain special artistic effects. When two pictures are handed over, using the special skills of underexposure or overexposure can produce unexpected artistic effects.

3. Exposure to adverse effects

Refers to the negative effect of increasing exposure and continuing exposure, but reducing the density.

4. Dark exposure

The exposure in which the dark exposure point of the exposure meter is aligned with the minimum measurement value is called dark exposure. Dark exposure makes the dark parts clear, and the rest are outside the effective light field of the negative film, which is bound to be overexposed, especially the brightest part of the picture is white hair. This method is suitable for shooting bright and soft tones.

5. Bright exposure

Measure the highest brightness of the scene in the selected light field, and use the exposure meter to aim at the bright exposure point with the highest brightness for exposure, which is called bright exposure. In this way, only the bright part of the selected light field can be photographed, and other faded parts are outside the effective light field on the negative, which will inevitably lead to underexposure and lack of layering. In the picture, the high-brightness parts are distinct, and the dark parts become shadows or silhouettes. This method is suitable for "dark tone" and "hard tone" pictures.

V. Photosensitivity

1. Sensitivity

A numerical value representing the exposure speed. Under the specified development conditions, the exposure required for photosensitive materials to reach a certain density value is certain, that is, sensitivity = constant. There are many international standards to measure sensitivity, such as China's Interim Standard (GB) and American National Enterprise Standard (ASA).

2. Photosensitive determination

According to the relationship between exposure and density, the method of testing the properties of photosensitive materials and controlling photographic and printing conditions. The photosensitive material is exposed in sensitometer step by step, and the specific curve corresponding to the exposure amount and density value is obtained after development, so that the sensitivity (exposure index), contrast coefficient (denoted by R), tolerance (brightness tolerance range) and other characteristic indexes of the photosensitive material can be measured. Wedges were developed in different periods. According to the corresponding relationship between contrast coefficient and development time, the function curve of r= f(t) is drawn as the basis for controlling development conditions.

VI. Clarity, Brightness and Visibility

1. Clear

Also known as "image boundary", the imaging ability of the photographic lens is clearly visible in the fine texture. The reflected light points of an object gather into a focus (actually a circle of dispersion) through a lens, and its size can determine the sharpness of the lens. If the diffusion circle is large, the image boundary of the lens must be soft and scattered, and fine texture cannot be displayed; If all the scattering circles are small and the synthesized image can distinguish the fine texture, then the image boundary of the lens can be said to be good. This belongs to optical clarity. In addition, the low resolution and overexposure of photographic negatives, as well as the strong properties of developers and inappropriate development methods will affect the clarity of images, which belongs to photographic clarity.

Step 2 be light

Photographic terminology. The visual brightness produced by light. Brightness is different from lightness, it is a subjective feeling and a psychological impression, which cannot be measured directly.

3. Visibility

Usually refers to the maximum distance that normal vision can see objects. Here refers to the clarity of the movie picture (reflected on the screen) seen by normal vision at a certain distance, so it is also called "brightness". Visibility is limited by many factors, such as the resolution of the camera, the weather and light when shooting.

Seven, photography and photography.

1. Photographic desktop

Also known as "photographic design". A specific shooting plan made to reflect the intention of photography creation. The photography table includes the design of the site, special effects and specific measures. Photographers should study every lens, from shooting angle to lighting, from shooting time to ambient atmosphere, from color tone to optical lens and optical accessories, from shooting method to technical measures. The photography platform is also the most concrete and meticulous shooting plan for photographers (elephants).

2. Photo exhibition

Working terms of film photographers and TV photographers before shooting. After accepting the shooting task, the photographer (cameraman) makes a comprehensive analysis of the film and television manuscript on the basis of listening to the director's opinions, and then explains to the film crew his understanding of the manuscript, the conception and requirements of the main scenes of the film and television textbook, etc. Because of different photographers' creations, the expression of photography ideas is also different, some are expressed in words, and some are expressed in words and sketches. Photographers (cameramen) must make a photographic exposition before shooting the film and television teaching materials, and communicate with other creative departments to unify their intentions in order to realize the photographic concept.