My preferred usage is to stick with 20ma and adjust the legnth of the period. Shown here is 20ema of 10day period.
More information can be learnt from 'endlessmountain' on youtube but only the very top and bottom levels are used with the High, Low & Close. Also i am not aware if this originates from any other source.
Thankyou to Clarke Moody and endlessmountain. Hope you like this tool.
Update: With interest gaining from the community i have decided to publish what is in my opinion a better version.
Upper and lower levels are now multiplications of 1.272 (square root of 1.618). See script for the percentages.
High and low shaded bands shows the average candle to wick range.
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.