Acutanceis the less understood characteristic of sharpness. Acutance isn’t about resolving detail, it’s about the transition between edges. In other words when an edge changes from one brightness level to another. This is whatSharpeningin digital parlance is all about. Scanning and digital capture softens acutance and so we apply a (ill-named) process called anUnsharp Maskto increase edge sharpness back to what it should be. Remember, this hasnothingto do with resolution, the other aspect of sharpness. Unfortunately some anti-digital Luddites still confuse the two.