Lens hood is a device installed on the front of photography lens, digital camera and video camera to block harmful light. It is also one of the most commonly used photography accessories. Lens hoods are made of metal, hard plastic, soft rubber and other materials. Most 135 lenses come standard with a hood, but some lenses need to be purchased separately. The models of shading devices used for different lenses are different and cannot be used interchangeably. The lens hood is an indispensable accessory for visible light lenses!
Strictly speaking, the lens hood is an integral part of the lens optical system. A lens is composed of several or dozens of lenses. Each lens has two reflective surfaces, and a lens has dozens of reflective surfaces! The more reflective surfaces, the greater the impact on the lens imaging! Especially when shooting with backlight or side backlight, multiple Reflective surfaces will interfere with each other to form a halo. Halo can make the picture look dull (colors are not saturated) or appear flared. Sometimes the picture taken seems to be covered with a layer of mist. In fact, this is caused by not using a lens hood, not the quality of the lens! The inner wall of a high-quality lens hood has undergone multiple matting treatments. The reflectivity of its inner wall is only about 10%, and it will not refract the lens when used. Using a shading device will play a good role and effect in suppressing picture halos, preventing stray light from entering the lens, blocking rain and snow splashes, protecting the camera and lens from accidental collisions, and giving full play to the potential optical qualities of the lens.
When taking outdoor photography, you should try to use a lens hood, which is very beneficial to improving the quality of your shots. A set of experiments were conducted under the same test conditions (side backlight, distant view). Two groups were photographed with and without the hood. Among them, the image quality of a group of pictures using a hood is greatly improved compared to a group of pictures without a hood! The performance is as follows: the halo in the sky in the upper right corner of the group of pictures using a hood disappears, and the color saturation of the picture and clarity are significantly improved.
