When using the RelativeDateFormat for Time Series charts (JFreeChart 1.0.13), the tick marks are not placed in a logical fashion. Instead, the tick marks and the corresponding labels appear where they would have before the new time base has been set. This results in tick marks and labels at locations such as 0h1m17s, 0h3m17s, 0h5m17s, etc. instead of the logical 0h0m0s, 0h2m0s, 0h4m0s. I have attached a file containing source code which displays this behavior. It is a slightly modified version of the RelativeDateFormatDemo1.java file included in the demo source.