The photos taken by SLR cameras are all black. Why?

There are several reasons why the photos taken by SLR cameras are black:

The photos taken by the SLR camera are black, which shows that the exposure is seriously insufficient when shooting.

The M gear you are using is a full manual gear. In the M file, you need to manually set the shutter speed and aperture, so that these two parameters can match, in order to take pictures correctly. Otherwise, the photo will be overexposed or underexposed, or the photo will be out of focus.

DSLR digital camera refers to a single-lens reflex digital camera, that is, digital, single-lens, lens and reflex.

Single lens reflex (SLR) is the most popular viewfinder system, which is used by most 35mm cameras. In this system, the unique design of the mirror and prism enables the photographer to directly observe the image passing through the lens from the viewfinder. Therefore, you can accurately see the same image that the film is about to "see".

SLR digital cameras have two main features. First, they can exchange lenses of different specifications, which is the inherent advantage of SLR cameras and incomparable to ordinary digital cameras. The second is to take pictures through the camera lens. Most of the traditional camera lenses with the same bayonet can also be used in digital SLR cameras. Digital SLR cameras are more expensive than ordinary household digital cameras, and SLR cameras are more suitable for professionals and photographers. The body and lens of most SLR cameras are sold separately.

The core of the SLR system is a movable mirror, which is placed in front of the film plane at an angle of 45. The light entering the lens is reflected upward by the mirror to a piece of ground glass. In order to correct this defect, today's eye-level SLR cameras are equipped with a pentaprism above the frosted glass. This prism reflects light many times to change the light path and send the image to the eyepiece. At this time, the ground image is upright up and down, and corrected left and right.

When framing, most of the light entering the camera is reflected upward by the reflector to the pentaprism. Shutters of SLR cameras are almost always directly in front of the film (because they are located in the film plane, they are called focal plane shutters). When framing, the shutter is closed and no light reaches the film. Press the shutter button, the reflector quickly turns up to get out of the way, at the same time, the shutter opens, the light reaches the film, and the shooting is completed. Then, the mirrors in most cameras will be reset immediately.