| Studies: Overlay |
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Overlay charts can be applied to a Host chart. This allows you to look
at 2 different charts in the same chart window. Overlay Charts
can also be subtracted or divided to create Spread Charts and Ratio Charts. The
original chart is called the 'Host' chart. An Overlay chart
is placed on the Host chart just like studies are placed on a chart. The
Overlay charts become 'Chart Objects' of the Host chart. The
Properties of Overlay Charts, Spread Charts, and Ratio Charts can be accessed
by clicking the Chart Objects button (or pressing Ctrl-O on
the keyboard).
Chart Overlays
The Overlay feature is used to open two or more charts in the same chart window. Chart
Overlays are used to compare relative movements between a Host chart and the
Overlay charts. An Overlay chart can be customized with its own colors,
chart scaling, and chart type. Each Overlay chart can also be offset
up or down, or multiplied by a number to adjust the scale of the chart. The
Overlay can also be inverted upside down.
To place an Overlay chart on a Host chart click the Studies button
and then select 'Overlay Chart'. The 'Chart Overlay' properties
window will be displayed. Type a chart filename in the 'Symbol' entry
box (ex. IBM ) and then click OK. The entered chart will
be overlaid on the Host chart.
The Overlay chart time frame will always be the same as the Host. For
example, a Daily chart can only be overlaid with other Daily charts. Entering
a filename extension (like .D for daily charts) is not necessary
for the Overlay chart name since the time frame will always match the Host
chart.
The Overlay chart will be synched-up with the Host chart so that each host
bar has a matching Overlay bar for each time period. If bars are missing
from the Overlay chart, a synthetic bar will be created to fill the time. Bars
that exist in the Overlay data but not in the Host will be skipped and not
displayed. In short, the Host chart is the master in which the Overlay
must coincide. Since an Overlay chart is a 'Chart Object' of
the Host chart, a request to remove all Chart Objects from the Host chart will
also remove the Overlay.
Spread Charts
A Spread Chart is created by subtracting an Overlay chart from a Host chart. Spread
charts can be opened in two ways.
1) Enter Symbol--Symbol in the Charts panel (example: IBM--MSFT.D). Note: There
are 2 minus signs that separate the symbols. The first symbol will be
the host, the second symbol will be the overlay spread symbol. Enter
the Time Frame after the 2nd symbol.
2) Add the Overlay study object to a Host chart, then specify the overlay ‘Chart
Type’. Open the Properties window for the Overlay, and then select 'Spread
Line' or 'Spread Chart' from the 'Chart Type' drop-down
list to cause the Overlay chart to be subtracted from the Host. For example,
to display a spread chart of IBM minus MSFT, first display
the IBM chart as the Host, then click the Studies button
and select 'Overlay Chart'. Enter MSFT in the 'Symbol' entry
box. Select 'Spread Chart' as the Chart Type and then click OK. The
resulting spread calculation will be displayed on the Host chart as either
a Line or as Spread Bars. Optional multipliers or price offsets can be
entered in the 'Parameters' panel to adjust the value of the Host
and Overlay chart data.
Note: The selections of 'Spread Chart' and 'Ratio Chart' will
plot as bars, where open prices give a specific point for the open evaluation,
close prices give the close evaluation, and then the high and low of the bars
is the maximum or minimum evaluations from the pairings. This is the
best reconstitution of the bar range that we can assemble after the fact from
the bar history.
Ratio Charts
A Ratio Chart is created by dividing an Overlay chart into a Host chart. Select 'Ratio
Line' or 'Ratio Chart' from the 'Chart Type' drop-down
list to cause the Overlay chart to be divided into the Host. For example,
to display a Gold and Silver ratio chart do the following. The following
example divides the July 2007 Silver chart into the June 2007 Gold chart. First
display the GC M7 chart as the host, then click on the Studies button
and select Overlay Chart. Enter SI N7 in the 'Chart' entry
box. Select 'Ratio Chart' as the Chart Type and then click OK. The
resulting ratio calculation will be displayed on the Host chart as Ratio Bars. Optional
multipliers or price offsets can be entered in the 'Parameters' panel
to adjust the value of the Host and Overlay chart data.
Chart Overlay Properties Window
Click the Chart Objects button to open the 'Chart Overlay' properties
window. The properties window is used to change the settings for the
Overlay chart. Click the Delete button to remove the Overlay
chart. Click the Delete All button to remove all Overlay
charts from the host chart.

Parameters
Study Lines
Grid Lines
If the Overlay is plotted in a study sub-window, the grid line color,
style, and different grid levels can be selected.
Keyboard Commands
The following keyboard keys can be used to adjust the scaling and height of
the Overlay chart.
We all seek a leading indicator that gives advance notice of what the market is going to do next. I have been watching the interaction of JNPR (Juniper Networks) and the June Nasdaq futures contact. At several key turning points in NQ M2, I see that JNPR is already leading the way, giving advance notice of what the NQ M2 market will do next. Permit me to share with you a three day sequence in comparing both charts using 5-minute intra-day bars.

On Monday, NQ M2 formed a wedge from the open until 12:00 (noon Central time). The question in the minds of NQ traders was whether the breakout from the wedge would be up or down. The JNPR chart was steadily lower all morning serving as an advance indicator that NQ would be going DOWN and not up.

On Tuesday, JNPR and NQ M2 both rallied until 10:30. NQ M2 put in a new high at 11:05, but JNPR did not. This is a first BIG clue that the 11:05 top in NQ M2 was going to be the daily high. At 14:10, NQ M2 was pushing higher for a possible retest of the 11:05 high, but JNPR was definitely in a downtrend. JNPR's 14:10 rally was nowhere near its mid-morning high. Again, JNPR served as an advance indicator that the NQ M2 retest of the high would fail, and NQ M2 would go lower.

Wednesday opened with a sharp sell-off in both JNPR and NQ M2. They both put in lows at 9:35. NQ M2 put in a new lower low at 10:30, but JNPR found support and did not put in a new low. Again, JNPR gave advance notice that the market would not continue lower. See the divergence that is marked on this chart. From the 10:30 lows, both JNPR and NQ M2 experienced significant rallies.
Have I found the crystal ball for NQ in the form of JNPR? I doubt it. Useful correlation found (with the benefit of hindsight) on three charts is not statistically sound. However, the trading tip being taught is that an individual stock may respond a bit quicker than a composite index. JNPR is a heavily traded Nasdaq stock, and I am seeing useful correlation where the e-mini Nasdaq future follows the direction set by JNPR. At least in the three day sequence documented in this article, JNPR was a worthy leading indicator. There was significant divergence at three key turning points in comparing JNPR behavior at these tops and bottoms with the NQ M2 behavior. NQ M2 followed the JNPR lead either higher or lower. When NQ M2 tried to go higher but JNPR was going lower, NQ M2 turned around and went lower. When NQ M2 tried to go lower, but JNPR would not follow lower, NQ M2 turned around and went higher. This is just the type of leading divergence indicator sought after by analysts who use studies to show confirmation and divergence.
Overlay History
In the past users creating custom symbols
with Setup | Custom Symbols form would often have a simple spread or ratio,
and yet lack having any back history. If the same formula can be
expressed in our Overlay study to do the spread or ratio, then you will
now be able to get some back history. Create the overlay, and when
it displays it makes the calculations by loading the chart files and syncing
the data bars. Ensign Windows has the answer because it plots the
spread or ratio on the chart.
The feature added was to automatically write the spread or ration calculations out as an Ensign chart file. The file written will always be the name Overlay, with the chart time frame for an extension, in the same folder as the source data, such as C:\Ensign\Minute. You can use Windows Explorer to rename the Overlay file to be the symbol you use for your custom symbol. And then viola, you have some back history for your custom symbol chart.