File:Ink Saver Main Brush Roller Time Chart.png

Formula
Rolling time = 100/([base consumption per second]*(1-((0.99*x-(0.09*x)^2)/(200/3))))

Base consumption per second while rolling:
 * Carbon Roller, Splat Roller, Dynamo Roller: 6
 * Inkbrush: 8.1
 * Octobrush: 10.8