After wiping the lens, the ghost problem on the camera lens was photographed.

This is a normal glare phenomenon, caused by the glare of the lens mirror, caused by the test lens itself, not because it is clean.

So why is there glare? This should start with the optical structure of the lens. Lenses are generally composed of multiple lenses, and each lens has two reflecting surfaces. A lens will have more than ten reflecting surfaces, and the lens surface will reflect about 5% of the incident light. The more reflective surfaces there are, the more times the light will be reflected and diffused after entering the lens, so the more complicated the lens is, the more the image quality will be affected. Especially when shooting with backlight or side backlight, high-intensity light source enters the lens, which makes multiple reflection surfaces interfere with each other and easily forms glare.

Methods of preventing lens glare

Use a hood

It can be said that the hood is an integral part of the lens optical system, which is widely used in backlight photography and can effectively prevent lens glare. Common shapes are cylindrical and petal-shaped, and the materials are probably: metal, plastic and rubber, and they are divided into different lengths, so you should choose a hood that matches the lens.

The inner wall of high-quality hood is treated by multiple extinction. The reflectivity of its inner wall is only about 10%, so it will not refract the lens itself when used. Using the hood not only has a significant effect on restraining the glare of the picture and preventing stray light from entering the lens, but also can stop the rain and snow from splashing and protect the camera and lens from accidental collision.

If the light source is too close to the hood, glare may still appear. At this time, you can cover the side of the light source with your hand or hat and extend the hood.

Adjust the angle

Now that we know the cause of glare, we should try to avoid it, so we should adjust the direction of the lens or light source to prevent the light source from facing the lens or being too close to the lens, observe the change of glare in the viewfinder, and press the shutter until we are satisfied.