Is the image effect of blue sun paper-cut generally negative?

Blue Sun Paper-cut Wenchuang is a traditional photography technique, which is made of iron salt sensitizer and paper. In the process of drying blue, the exposed paper will appear blue tone, while the blocked part will remain white and light color. The image effect created by blue paper-cutting is negative, that is, the white and light-colored parts represent the solid part of the original image, and the blue part represents the blank and transparent part of the original image. This negative effect makes Qinggan paper-cut literary creation have unique artistic style and visual effect.