When part of the image is unsharp as a stylistic effect, or the emulation of "realistic" effects, such as looking through certain materials, in-image photographs that are blurry, etc.

Do not confuse

• depth_of_field, which is a realistic effect of lenses related to focus.
• motion_blur, which is a realistic effect of shutters and similar created by fast movement of an object.
• bad quality scans, photographs, etc. (which should generally not be uploaded)
• heavily denoised scans.

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