Is it still useful to take blind watermark photos?

The useless blind watermark photography is to add a watermark that can't be detected by naked eyes when taking pictures in Zhihu, which is mainly used in occasions with confidentiality requirements. According to relevant information, this function went offline on September 24, 2022, and it is useless. Photography, also known as photography, generally refers to the process of exposing the photosensitive medium through the light reflected by the object, usually using a mechanical camera or a digital camera.