What is the letter of automatic mode on SLR cameras?

The letter of auto mode on SLR cameras is auto.

Application of fully automatic mode;

Automatic mode is also commonly known as "fool mode", just like a fool camera.

It basically does not need to manually adjust various parameters, nor does it need to consider environmental factors. It only needs to pick up the camera to make a good composition and press the shutter to complete a photo shoot, which is very suitable for beginners.

Because all the parameters are determined by the camera's recognition of environmental factors, sometimes the settings are inaccurate. If you want to take professional photos, don't rely too much on this mode in an emergency.

Extended data

Advantages of SLR cameras:

It only has one lens, which is used for taking pictures and framing, so the parallax problem is basically solved.

When taking a view, the light emitted by the object is focused by the lens, reflected by the oblique mirror to form an image, and then reflected by the "roof prism" raised at the top. Photographers can observe the scene through the eyepiece, and it is the same image as the scene, which is convenient for framing and focusing.

When shooting, the mirror will bounce up immediately, the lens aperture will automatically shrink to a predetermined value, and the shutter will open to make the film sensitive; After exposure, the shutter is closed and the aperture of the mirror and lens is reset at the same time.

Single-lens reflex cameras can be replaced by various wide-angle, medium-focus, telephoto or zoom lenses, and can also be equipped with close-up lenses, telescopic rings or telescopic leather cavities as needed.

In short, any scene that can be seen clearly from the viewfinder can be photographed by the camera.