Acutance is synonomous with sharpness- the way two areas of different densities on a negative meet to form a line- "hard" lines result from high acutance developers, indistinct lines is characteristic of poor acutance. Most high-actuance developers are described as grainy, but the sharpness makes up for this IMO. Many fine-grain developers suffer from poor acutance, IMO.(posted 8148 days ago)I'll let someone else tackle tonality.