Hierarchy classification:

1. top of the aat hierarchies
2. Activities Facet
3. Processes and Techniques (hierarchy name)
4. [processes and techniques by specific type]
5. [image-making processes and techniques]
6. [photography and photographic processes and techniques]
7. photographic techniques
8. [photographic processing and presentation techniques]
9. masking (photographic process)

Anotations

Scope note:

An image sharpening technique introduced in Germany in the 1930s that increases the perceived acutance of photographic images. This is achieved through the use of an intermediate positive that is slightly blurred coupled with the original negative. When light is projected through the in-register negative and positive, some information is cancelled from the negative. The original photomechanical process has been reproduced in digital image processing to achieve a similar effect.