SLR cameras shoot things with A4 white paper pads. What is the cause of lavender effect?

This is caused by the white balance setting of the camera.

Generally speaking, in different light and shadow environments, the color temperature captured by the camera is different (for example, it will be blue on cloudy days, yellow at dusk, green on trees and so on). ), and the white balance setting can make white appear "relatively correct" in different environments. For example, on a cloudy day, the camera's automatic white balance can increase yellow and decrease blue, offset the blue component in the environment, and make the picture look normal, and the white in the picture is relatively white.

But in many cases, the camera's automatic judgment is not always accurate, and misjudgment often occurs, so the color taken is not as accurate as it looks with the naked eye, so this situation is normal.

Photographers usually have two solutions to this situation:

1。 When the ambient light changes slightly, the white balance should be set manually and judged by people to achieve more accurate color representation.

2。 When the ambient light changes greatly, the white balance is fixed. Although the color obtained under white balance is not necessarily accurate, the color relationship of light changes can still be accurately recorded, just like if you use a scale, even if the scale is not accurate, you can still use it to measure the weight difference of different objects. This can facilitate batch adjustment of white balance in the later period.