Here is a script to use 3 types of Bollinger Bands.
It is like three resistances or ranges in wich the Chart generally likes to move. A 1, 2 and 3 Width BB. The Chart moves 90% between the yellow one.
As support for my study i use the 13 EMA. is the Chart over the 13 EMA and under the Yellow (2) BB the trend is bullish. Is t under the 13 EMA and over the...
With this script you can use bollinger bands with up to 4 moving averages.
The bollinger band basis and the moving averages can be changed to EMA's.
To prevent auto scaling of the bands, turn off the plots and just keep the fill.