 DarkLight
Standard Deviation Channel (SDC)
 DarkLight
Standard Deviation Channel (SDC) is a channel that consists of a linear regression line in the middle and support/resistance levels, which are standard deviations placed equidistantly above and below the middle line.
The middle line is calculated as the linear regression for each bar:
y = a + bx
b = (nΣxy  ΣxΣy) / ( nΣx^{2}  (Σx)^{2} ))
a = (Σy  bΣx) / n
where:
y – the data price source
x – the number of bars
a – the constant (the value when x equals zero)
b – the slope of the line
n – the number of data points selected
The standard deviation is calculated as follows:
StdDev = SQRT [SUM (Close_{n1}  SMA_{n})^2)/N]
where:
SMA – nperiod Simple Moving Average for current bar
Close – close price for each of the past n periods
N – calculation period
INPUTS
Input  Description 

Length  The number of bars used to calculate the Standard Deviation Channel 
Price 

The following data sources are available for the price:

Input  Description 

Deviations  The number of standard deviations between the Linear Regression Trendline and support/resistance lines 
PLOTS
The plot renders the data you are working with on the chart. You can show/hide a plot by clicking the corresponding item in the settings. Every plot has a set of basic settings that you can change: color, weight, and type.
Plot  Description 

LinReg  The Linear Regression Trendline plot 
Resistance  The upper border of the Standard Deviation Channel 
Support  The lower border of the Standard Deviation Channel 
Color 

Click the color rectangle under the plot's name to open the palette. Use the slider at the bottom to set the opacity of the color. To create a custom color:
The customcreated colors are added to your palette. To remove a custom color, drag it out of the palette. 
Weight 
Change the value (in px) to adjust the thickness of the plot. 
Type 
The following plot types are available:

OVERLAYING
Check Overlaying to display the indicator on the chart. Otherwise, the indicator is shown in a study pane down below.