Choosing A Time Bar Length In Intraday Trading by Cynthia Kase
Most intraday technical traders use charts based on hours or fractions of an hour. Most trading days, however, don't divide evenly into hours or conventional time fractions such as 30 or 45 minutes. Here are some suggestions from an intraday trader on how to handle bar lengths.
For periods longer than about 15 minutes, I suggest one of two methods: Either divide the number of
minutes in a day into same-length bars, or divide the day into bar lengths such that the leftover bars cover
the last five to 10 minutes of the day, thus giving the indicators a heavier weighting of the closing time
period. You will need software that provides intraday charts in a variable-minute format.