Maxtone is referred to as hybrid or mixed-dot screening. By using Maxtone, you can potentially preserve the entire dynamic range, with smooth transitions to 0%.
Full highlight gradient with Maxtone
Maxtone mixes elements of AM and FM (stochastic) screening in highlight areas. (Maxtone can be used in shadow areas, but few if any printers actually use it in this way. The appearance of Maxtone in shadows can resemble press picking, and is generally avoided for that reason.)
To implement Maxtone, you must know the minimum dot value for a given media and line frequency. When Maxtone is applied, full AM screening will be used down to the minimum dot point. At the point at which it is no longer possible to hold a smaller dot on plate, the screening will switch to a fixed dot size. Maxtone will randomly remove dots to accurately portray different tonal values using the same size dot. For example, if Maxtone is set to be the size of a 6% dot, then at the 3% tonal area, only half as many dots will be used as the 6% tonal area.
With normal AM screening, highlights are lost
With Maxtone, all highlight screening is preserved
With Maxtone, full highlight tonal range can be preserved
It is important to note that although Maxtone is a stochastic technique, the actual Maxtone dots only appear on the AM grid points. Other hybrid screening technologies will sometimes move their dots off the grid in an attempt to improve visual appearance. Kodak testing has shown that at the point where you switch from on-the-grid AM to off-the-grid FM, there is an unacceptable increase in dot gain. By leaving Maxtone on the grid, there is no visible tone jump in the transition from AM to Maxtone, and gradients appear smooth.