Perspective v7.6
Subbottom & Sidescan Processing
Detailed Self-Guided Tutorial
-- Lake Champlain, USA --
By:
Tony M. Ramirez
November 2013
Triton Imaging Inc.
Engineering Office
2121 41st Avenue, Suite 211
Capitola, CA 95010
USA
+1-831-722-7373
+1-831-475-8446
sales@tritonimaginginc.com
support@tritonimaginginc.com
© 2013 TRITON
This software tutorial is provided as a means to become familiar with TRITON’s software through following a series
of steps for processing subbottom and sidescan data using the associated datasets. The user interface presented in
this guide is subject to change to accommodate software upgrades and revisions. While every precaution has been
taken to eliminate errors in this guide, TRITON assumes no responsibility for errors in this document.
Users of this document are required to have a valid license for Perspective, MosaicOne and BathyOne in order to
activate the software.
TRITON hereby grants licensees of TRITON’s software the right to reproduce this
document for internal use only.
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Table of Contents
INTRODUCTION ..................................................................................... 1
HOW TO USE THIS GUIDE ........................................................................ 1
I. PROJECT SETUP ................................................................................. 2
STEP 1: Extract files to your local drive .................................................................................................................... 2
STEP 2: Start Perspective and check Program Settings ........................................................................................... 2
STEP 3: Import GeoTiff files ..................................................................................................................................... 3
STEP 4: Import Feature and Vector files .................................................................................................................. 4
STEP 5: Zoom / Set Region / Set Custom Cursor / Save Project .............................................................................. 6
II. SUBBOTTOM PROCESSING ................................................................... 8
STEP 6: Import Raw Edgetech SB216 Data Files ...................................................................................................... 8
STEP 7: Process navigation for imported files following these steps ...................................................................... 9
STEP 8: Open Subbottom Profiles .......................................................................................................................... 10
STEP 9: Bottom Track All Lines ............................................................................................................................... 11
STEP 10: Convert Bottom Track to Reflector ......................................................................................................... 12
STEP 11: Process Subbottom Profiles .................................................................................................................... 12
STEP 12: Import Raw Knudsen Pinger Data Files ................................................................................................... 14
STEP 13: Repeat Steps 7 through 11 for the Knudsen Pinger Data ....................................................................... 15
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III. SUBBOTTOM INTERPRETATION OPTIONS............................................... 17
STEP 14: Track/Digitize Reflectors ......................................................................................................................... 17
STEP 15: Check Intersections ................................................................................................................................. 18
STEP 16: Folded Profiles ......................................................................................................................................... 19
STEP 17: Display Borehole Data ............................................................................................................................. 20
STEP 18: Profile Measurements ............................................................................................................................. 21
IV. SIDESCAN PROCESSING..................................................................... 23
STEP 19: Import Raw Klein 3000 Sidescan Data Files ............................................................................................ 23
STEP 20: Process navigation for imported sidescan data following these steps ................................................... 24
STEP 21: View Waterfall and Enhance Display ...................................................................................................... 26
STEP 22: Verify Bottom Tracking............................................................................................................................ 28
STEP 23: Create TVG Curve .................................................................................................................................... 32
STEP 24: Create Mosaic - High Frequency Channels ............................................................................................. 34
STEP 24: Create Mosaic - Low Frequency Channels ............................................................................................. 37
STEP 25: Review Results......................................................................................................................................... 38
V. DATA FUSION ................................................................................. 39
VI. EXPORTING/FINAL PRODUCTS ............................................................. 40
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INTRODUCTION
The 'LakeChamplain' dataset is provided by Triton for use as a training tool for Triton
Perspective as well as for new users who wish to test the software's capabilities. This
guide was written using Perspective software version 7.6.4.0.
The demo project files are provided in four parts, with two options for the Edgetech
subbottom data files.
1. LakeChamplain.zip (115 MB)
2. Edgetech SB216.zip (553 MB) or
Edgetech SB216c.zip (154 MB)
3. KnudsenPinger.zip (47 MB)
4. Klein3000.zip (125 MB)
Demo datasets in this project include an Edgetech subbottom survey in Lake Champlain
using their SB216 portable profiler (full lines or clipped), a coinciding sidescan survey
line collected with a Klein 3000 dual-frequency sonar, and to the south along the river
another subbottom profile collected using a Knudsen Pinger.
Note, this guide assumes that Triton Perspective is installed and licensed. If you need
a demo license to run Triton software, please email sales@tritonimaginginc.com.
HOW TO USE THIS GUIDE
This guide is divided into seven major sections, starting with Project Setup and ending
with Exporting/Final Products. Within each section are a series of continuous steps to
follow to create the demo project and process the included datasets. Note that each
Step defines a task that may include several tasks to complete.
Many of the steps to complete are not described in full detail, but an attempt was
made in most cases to give some instruction on how to accomplish the task. However,
this document was created to be used in conjunction with the standard Perspective
processing guides, both as means to keep this document from being too large, and
also to help users become familiar with the processing guides and how to use them to
get the most from their collected datasets.
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I. PROJECT SETUP
STEP 1: Extract files to your local drive
 Create a folder called "TritonDemos" on the root level of the local hard drive you
will work from
 Extract the data from the zip files to the TritonDemos folder. Your project
directory should look like:
C:\TritonDemos\LakeChamplain
\Data
\EdgetechSB216 (or \EdgetechSB216c)
\Klein3000
\KnudsenPinger
\Features
\GeoTiffs
\Mosaics
\Reflectors
\Targets
\Vectors
STEP 2: Start Perspective and check Program Settings
 Launch Perspective, open the Program Settings by selecting the
toolbar button shown right
 Verify the following settings:
-- 'General' tab:
o set Working directory (C:\TritonDemos\LakeChamplain)
o set file path for GeoTiff Optimization Files and check the Optimize box
(C:\TritonDemos\LakeChamplain\GeoTiffs\Scratch)
o set the number of cores to the maximum number your computer has
o under Options:
 uncheck the box for 'Load Zoom Out'
 uncheck box for 'Launch Wizard on Import'
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-- 'Subbottom' tab:
o uncheck box for 'Show intersections in map view'
o change Reflector File Directory to "Specific Directory" and set to:
(C:\TritonDemos\LakeChamplain\Reflectors)
STEP 3: Import GeoTiff files
-- from C:\TritonDemos\LakeChamplain\GeoTiffs\
 Using the File menu, select Import/GeoTiff File... Navigate to the GeoTiff folder
and select all images
 When asked for a projection, select the following as shown in the image below:
 Universal Transverse Mercator
 Zone 18 North
 WGS84
 On the last page of the projection wizard, select 'Finish and Save'. Enter the
following name for the saved projection: UTM18N-WGS84
 After import, re-order the GeoTiffs in the file tree using the Move options in the
right-click menu so the final order of the GeoTiffs is:






NAIP_1M_2008_UTM18N.tif
sat_imagery_UTM18N.tif
TopoMap_UTM18N.tif
14783_11_UTM18N.tif
highway_map_UTM18N.tif
geologic_units_UTM18N.tif
TOP
BOTTOM
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 To allow us to see through the highway map image, right-click on the image and
select 'Color Settings' and change Opacity = 0.4, Contrast = 2.0
-- Note that increasing the contrast on a slightly opaque image can enhance the
foreground while making the background less prominent.
 Turn off the TopoMap_UTM18N.tif and 14783_11_UTM18N.tif images by
unchecking the boxes in the Background file tree next to the image names
STEP 4: Import Feature and Vector files
-- FEATURES
In Perspective, 'Features' are text files that represent information at the indicated
location. Features were first developed to allow users to show subsurface
lithologies on subbottom profiles. Since then the use of the point source
information files has expanded to include showing SVP and tide stations, wrecks
identified in the area, and any other point information that may be useful.
PART 1: Before importing Features,
first Feature Groups must be created.
 Right-click on the Features file
tree node and select
'Add/Edit/Remove Feature
Group'. This will launch the
dialog shown right.
 To create Feature Groups, follow
these steps:
1. Enter Name
2. Select Color
3. Select Symbol
4. Click 'Add'
5. Repeat until all groups are added
 Add the Feature Groups shown in the dialog above with the selected colors
and symbols, and when finished click the 'OK' button
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PART 2: Now that Feature Groups have been created, we can add our text files to
the appropriate group.
 Right-click on the group name in the Features file tree and select 'Add'.
 Browse to the C:\TritonDemos\LakeChamplain\Features folder, change the
file type in the bottom drop down menu to .CSV, and select the file to be
imported.
After adding each file to the correct Feature Group, your
file tree should look like the image shown right.
By default, all points added to feature groups are
displayed in the map view with labels turned on.
Uncheck boxes in the file tree to hide a Feature or
Feature Group. To turn labels on or off, right-click on
the Feature Group name and select 'Labels - all on' or
'Labels - all off'.
 Before proceeding, turn off labels for Soundings.
-- VECTORS
Vector files are DXF formatted AutoCAD files that
represent point, polyline, or polygon information at the indicated location.
 Import vector files by right-clicking on the Vectors node of the file tree and
selecting 'Add'
There is only one vector file for this project located in the folder:
C:\TritonDemos\LakeChamplain\Vectors.
 Select the SHORELINE_UTM18N.DXF file and click Open.
-- Note: When the projection dialog pops-up, make sure the import projection
is UTM 18 North, WGS84. If the dialog indicates the current import
projection is Unprojected (Latitude/Longitude), then click 'No' and select the
saved "UTM18N-WGS84" projection in the wizard.
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After the shoreline has
been imported, it is good to
change the Pen Settings so
it stands out better against
the map view backdrop.
 Change color to black by clicking on the existing color in the dialog above and
selecting black from the color pallet
STEP 5: Zoom / Set Region / Set Custom Cursor / Save Project
Before we save our project and start importing survey data for processing, we should
first define a region for the full extent of our project.
 ZOOM: Zoom into the map to include both of the satellite images plus all of the
point information loaded both as Features and as Vectors.
 SET REGION: Regions are defined by the current zoom extent. Create a region by
right-clicking on the Annotations/Regions file tree node and selecting 'Add Viewport'
(or by pressing F12). Name the region "Project Extent"
 SET CUSTOM CURSOR: The info display in Perspective always shows the cursor
location in the current UTM zone as well as in latitude-longitude. However if you
work in a different project it is possible to see the cursor position in other
coordinates using the custom cursor at the base of the window. Click the button on
the Custom Cursor panel and using the
Projection wizard, select from the
standard projections or enter a
custom projection.
-- For this project, select the following
as shown in the image to the right:
 State Plane
 Vermont
 US Survey Feet
 NAD83
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-- Once selected, click Finish and Save and name the projection as shown below:
Please note that this Custom Cursor panel can be minimized to increase the size of
the map view by clicking on the Thumbnail icon in the upper right corner of the
panel as indicated by the red circle below.
 SAVE PROJECT: Before proceeding, it is wise to save the project! From the File
menu, select Save Project As. Save the file to the root project directory as:
"LakeChamplainDemo"
At this point your project should like the image shown above with background
imagery, vector shoreline file, and point features loaded.
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II. SUBBOTTOM PROCESSING
There are two subbottom datasets available for this project; one includes 6 lines collected
with an Edgetech SB216 subbottom profiler, and the other includes only one line
collected with a Knudsen Pinger.
STEP 6: Import Raw Edgetech SB216 Data Files
Due to the size of the Edgetech dataset, a clipped version of the data is available that
only contains 4 lines all of which have been clipped to reduce the file sizes. Please
note that the clipped dataset still provides all of the functionality of the larger dataset
for the purpose of this tutorial.
 Using the File menu, select Import/Raw Data File... Navigate to the
.../Data/ EdgetechSB216 folder and select all six SEG files
-- Note: importing survey data files will extract the navigation from the raw data
files, draw the navigation lines in the map view, and create cache files for
storing information from the processing steps.
The next step is to zoom into the subbottom navigation and set a region for returning
to the full extent of the Edgetech data.
 Zoom into the imported data navigation lines using the Zoom toolbar button
and draw a box around the area to zoom into
 Once satisfied with the zoom extent, in the
Annotations file tree right-click on Regions
and select 'Add Viewport' , and name this
region "Edgetech SB216"
 Right-click on the region in the file tree and
open Color Settings to change the color to
purple
At this point your map view should look like the
image shown right. The blue lines represent
survey navigation lines with arrows pointing in
the direction the data was collected.
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STEP 7: Process navigation for imported files following these steps
Before looking at the subbottom profiles it is important to process the navigation.
Navigation processing can be performed on a single line at a time or on all lines in
the 'Navigation/Subbottom' file tree.
 Right-click on the Navigation/Subbottom file tree node and select
Process Navigation...
-- For more information on navigation processing options, please refer to the
navigation processing guide (Perspective_NavigationProcessing_Guide.pdf).
 In the Process Navigation dialog, click on the Filter Setup button to open the
BoxCar settings. Select:
 Window Size = 30
 Number of iterations = 1
 Source = Sensor
 Heading = Course Made Good
 Layback = None
 Speed = Off
 Click OK to close the BoxCar Settings dialog and then select Process to run the
BoxCar filter on the navigation data. Because this was done on the root
Subbottom navigation node in the file tree, all lines will be processed at the same
time using these parameters.
For repeat processing of the navigation
data, increase the number of iterations
to set the number of passes through the
processing algorithm. This allows for
further smoothing of the navigation.
When finished the Process Navigation
dialog should look like the image to the
right.
 Click Exit to close the dialog.
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STEP 8: Open Subbottom Profiles
Processing of the subbottom profiles in Perspective is performed using filters and
tools found in the Profile Settings dialog.
-- It is important to note that when applying Profile Settings it is possible to apply
them to one line or to all open lines at the same time. Also since there are
several pages to the Profile Settings dialog, it is possible to apply just the
settings from the current page or the settings from all pages at once.
To allow us to process all subbottom lines simultaneously we will use the option to
open all profiles loaded in the project at once.
 Right-click on the Navigation/Subbottom file tree node and select
View All...
Once the lines open its best to arrange them on a second monitor to allow the
map view to not be blocked while viewing the profiles. Since there are six lines,
they can be arranged as shown below:
By viewing all lines at the same time we can immediately see the effects of each
processing step.
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STEP 9: Bottom Track All Lines
The primary reason to bottom track subbottom profiles is the bottom tracking
results can be used to automatically generate the water bottom reflector.
-- This reflector is commonly used for applying the TVG (time-varied gain)
adjustments, and when used applies the TVG from the water bottom
downwards instead of from the top of the water column.
 Open the Profile Settings from any of the profiles using the toolbar button
or from the View menu, and switch to the Bottom Track tab
 To bottom track all lines simultaneously, you need to change the Profile
dropdown at the bottom of the setting dialog to All.
 Change the Bottom Track settings as shown in the dialog below and then click
Compute for All
This will draw a red line on each profile showing the results.
-- Note the Level sets the strength of the return, Holdoff sets the minimum depth
to get below water surface reflections, and Delta sets the size of the filter gate.
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STEP 10: Convert Bottom Track to Reflector
This has to be done for each profile
individually and is accomplished from the
Reflector tab of the profile Information display
as shown right
 For each profile, right-click on the R0 reflector in the Reflector tab and
select Auto Generate Seabed
 After the water bottom reflector is generated for each line, select the
Show/Hide Bottom Track toolbar button
in the Profile display to hide the
bottom track
-- When converting the bottom track into the water bottom R0 reflector, spikes
that were seen in the bottom track results can result in spikes in the water
bottom. Before proceeding it is best to remove those spikes so the water
bottom reflector closely matches the seabed.
 For each profile, maximize the profile so it fills the whole monitor
 using the 'Select' toolbar button
left-click on the nodes not on the
seabed and drag them to the correct depth
 Restore each profile window to its reduced size after correcting the water
bottom reflector
-- The water bottom reflector will be used for the TVG filter and should be defined
before applying filters.
STEP 11: Process Subbottom Profiles
SIGNAL SETTINGS
 in the 'Signal' tab of the Profile Settings, set the following:
o Rectification = "Rect" sets all signals to positive (good for digital data)
o Vertical Downsampling = "Max" due to more samples per trace than pixels in the monitor
o Horizontal Downsampling = "Avg" due to more shots per line than pixels in the monitor
 Click the 'Apply Signal Settings to All' (make sure Profile = 'All')
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TIME/VELOCITY SETTINGS
 in the 'Time/Velocity' tab of the Profile Settings, set the 'Viewable Vertical
Range' as follows:
o Start = "5" sets all profile display to start at 5ms
o Depth = "55" sets the duration of the viewable range
 Click the 'Apply Time/Velocity Settings to All'
This will set the viewable range to start at 5ms and continue for 55ms down to
60ms, focusing on the area of the profiles with usable information. The advantage
of setting the viewable range over using the zoom tool is this becomes the home
zoom so the user can ignore the deep washed out sections of the profiles as well as
the water column above the seabed.
FILTER SETTINGS
 in the Filter' tab of the Profile Settings, set the
following:
o Stack: check box 'On', set size = 3
o TVG: check box 'On', check box 'From Seabed', click
button to open TVG Settings and set 'Custom Linear' to 0.70 dB/m as shown above
 Click the 'Apply Filter Settings to All'
This works fairly well for most profiles but profile EW1 was already fairly dark and
did not need as much gain increase as the other profiles.
 In the Profile Setting dialog, change the profile selection from 'All' to only 'EW1'
 in the TVG Settings, change the Custom Linear to 0.30 dB/m
 Click the 'Apply Filter Settings to P1'
Applying filters to all profiles at one time generally only works if the power and gain
settings are not changed between lines during data acquisition. Also areas covered
with sands or gravels may require more gain since less energy will penetrate the
seabed.
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LUT SETTINGS
LUT settings allow the user to change the color pallet, how the color pallet is stretched
over the data range (invert, clip, rotation options), with the ability to apply a flat gain
to the profile. For this dataset the defaults work well and this page can be skipped.
 before proceeding, play with the Invert, Clip, & Rotation options to see how they
affect the color map display, be sure to return to the default setting once finished
ANNOTATION SETTINGS
This tab sets what is viewable in the profile window.
 before proceeding, try turning off the Rulers and Grids to see the affect, be sure
to return to the default setting once finished
CHANNEL SETTINGS
For data with multiple channels, this tab allows the user to select which channel to
display. Please note the user can also switch to the 'next' channel in the profile
window by selecting the Next Channel toolbar button:
FEATURE SETTINGS
This tab is used to project Feature files that contain subsurface information onto
the profiles. These options will be discussed later in Step 20.
STEP 12: Import Raw Knudsen Pinger Data Files
 using the File menu, select Import/Raw Data File... Navigate to the
.../Data/ KnudsenPinger folder and select:
15-LC1_100710_CHP15.0_FLT_001.sgy.
 click on the 'ProjectExtent' region in the Annotation file tree to zoom out
 use the Zoom toolbar button
to zoom into the Knudsen subbottom line
-- You can highlight the line by selecting it in the Navigation/Subbottom file tree
and the line will turn light blue in the map display.
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 Once satisfied with the zoom extent, press the F12 button on your keyboard to
quickly 'Add Viewport', and name this region "Knudsen Pinger"
 Right-click on the region in the file tree and open Color Settings to change the
color to purple
STEP 13: Repeat Steps 7 through 11 for the Knudsen Pinger Data
 Step 7: use same settings
 Step 8: right-click on navigation line and select 'View'
 Step 9: try with same settings (Level = 15%, Holdoff = 5ms, Delta = 0.18ms)
Note that some of the results are past the bottom indicating the Level is too high.
 Step 9 again: try with same settings except Level = 10%
By reducing the amplitude level percentage, the bottom tracking is improved!
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 Step 10: use same procedure
 Step 11: since this is analog data, some of the options are different from
processing digital data.
SIGNAL SETTINGS
 In the 'Signal' tab of the Profile Settings, set the following:
o Rectification = "None" keeps both positive and negative signals (very
important for analog data!)
 Click the 'Apply Signal Settings to P7' (make sure Profile = 'P7')
TIME/VELOCITY SETTINGS
 In the 'Time/Velocity' tab of the Profile Settings, set the 'Viewable
Vertical Range' as follows:
o Start = "10" sets all profile display to start at 10ms
o Depth = "0" shows the full record depth
 Click the 'Apply Time/Velocity Settings to P7'
FILTER SETTINGS
 In the Filter' tab of the Profile Settings, set the following:
o Stack: check box 'On', set size = 7
o TVG: check box 'On', check box 'From Seabed', click button to open TVG
Settings and set 'Custom Linear' to 1.00 dB/m as shown in the dialog above
LUT SETTINGS
Since this is analog data we can use a bipolar color map to show off the positive
and negative signals.
 Select the Bi-Polar #1 color map
 Add a Flat Gain = 7 dB, then click 'Apply LUT Settings to P7'
Applying a flat gain in addition to the TVG helps keep the deep sections from
getting too dark for this dataset.
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III. SUBBOTTOM INTERPRETATION OPTIONS
At this stage we should have fully processed subbottom profiles with the water bottom
reflector defined for each profile. Additional reflectors can now be added for layers
below the water bottom and to define faults or discontinuities seen in the profiles.
STEP 14: Track/Digitize Reflectors
As new reflectors are added to a profile, it will appear in the reflector list on all
profiles in the project, allowing for correlation between intersecting profiles.
 For each profile, maximize the profile so it fills the whole monitor
 Right-click in the Reflectors tab and select
'Add Reflector' as shown right, change the
name of the reflector to "Unconformity"
and click OK
 Right-click on the Unconformity reflector,
select "Line Color", and set the color to
Yellow
 Using the 'Digitize' toolbar button
left-click along the unconformity
between the upper relatively flat sediment layers and the folded
sediment layers below as shown in this image:
Note that I
used the
zoom/pan
tools to get a
better view of
the sediment
boundary to
help track the
horizon!
Page 17
 Repeat this process for the basement horizon: add reflector called
"Basement"; change line color to orange; use digitize toolbar button to
trace horizon below the folded sediment layers as shown below:
Reflectors can also be
digitized by holding
down the SHIFT key
and the left mouse
button and tracing
along the horizon.
To break a reflector across a span
where the reflector can't be defined, in
digitize mode select the node next to
the span and select CTRL-B.
 Restore this profile window to its reduced size after digitizing the
Unconformity and Basement reflectors and repeat this process for the
other profiles loaded in the project.
When finished, all profiles should have the Water
Bottom, Unconformity and Basement reflectors
digitized!
STEP 15: Check Intersections
Intersecting lines in the subbottom profile window
display as red vertical lines indicating the location of the
crossing profile. In addition to showing the along track
location of the crossing profile, also displayed are the
locations of the digitized reflectors on the crossing
profiles as shown in the image to the right.
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This is very useful for verifying reflectors meet at interseting lines and are called the
same name. When digitizing many
horizons in a profile, it is easy to call
a horizon H4 on one profile and the
same horizon as H5 on another. This
image shows how this can happen.
 For each profile, review reflector
intersections to verify compliance with reflectors picked on intersecting profiles.
For areas where the reflectors do not meet at the intersection, review both
profiles and adjust the reflectors until they do meet.
STEP 16: Folded Profiles
Another way to see how reflectors meet at intersecting survey lines is using the
Folded Profile tool in Perspective. Before digital records of subbottom data,
proifiles were printed on paper and often folded along intersecting lines to see how
well they align.
The Folded Profile tool simultes this capability digitally and is launched by clicking
the following toolbar button in the main Perspective window:
Clicking this button will open an empty profile window. To add data to the profile
window, click on connecting segments of subbottom survey lines in the map view.
When clicking on survey lines, the section clicked on
(bounded by either line intersections or the end of the
line) will be added to the Folded Profile window. The
image to the right shows the segments clicked on and
their corresponding profile IDs.
 Click on the Folded Profile toolbar button and add
the 4 segments shown in the image to the folded
profile window.
-- Be sure to click on connecting segments to see how reflectors cross the
intersection!
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Shown below is the folded profile window with segments from P0, P1, P2, and P5
added.
It is important to note that some segments may be darker than others due to TVG
and gain adjustments applied to each profile. To equalize the gain across the
folded profile view, open the individual profiles to adjust the filters. When applying
changes to the profiles, those changes will also update the folded profile view!
STEP 17: Display Borehole Data
Previously in this project we loaded CSV files as "Features" in the map view. Some
of these Feature files contained subsurface information from cores and borehole
collected in the project area.
This subsurface data can be
displayed on the subbottom
profiles by using the Features
tab in the Profile Settings.
Displayed on the right side on
this setting tab is a list of all of
the unique sample types
identified in the imported
Feature files associated with a
color. On the left side of the tab
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is a list of the Feature files loaded in the project, with a checkbox for indicating
whether or not to project them onto the profile display. Below this is a Line
Thickness setting and the ability to set how far to project the subsurface
information.
Note: to determine how far subsurface
data is located from the subbottom
survey lines, either use the Measure
tool in the map view to manually
measure the distances, or you can use
the Information option for the loaded
Features files. Right-clicking on a
Feature file in the file tree brings up the
option to view Information for that
Feature as shown to the right. The
bottom of the information dialog
displays the distances to each of the
profiles loaded in the project, and from
the feature list in the top right you can move to different features quickly to get
their information as well.
 Open the Profile Settings for one of the profiles, make sure the drop-down
menu at the bottom indicates all profiles, check the boxes for Boreholes and
Cores, set the Display distance to 200 meters and then click Apply.
 To better see the boreholes on the profile displays, set the Line Thickness = 7
and click Apply
-- Note: In addition to sediment types, Features allow the user to project any
down-hole data onto the subbottom profiles, including Shear Strength,
Friction Angle, Relative Density, etc.
STEP 18: Profile Measurements
Another interpretation tool in the subbottom profile window is the Measure tool
launched from the toolbar button:
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Clicking on the Measure toolbar button will automatically switch to the Measure tab of
the information display. Drawing on the profile with the Measure button active will
tell the user the horizontal and vertical distances, the true distance, plus the slope of
the drawn line. In subbottom profiles, there is often a very large vertical exxageration
required to fit the whole profile on the screen at once plus allow enough resolution in
the vertical to see the data. This exxageration often makes shallow slopes appear
almost vertical in the profile display. Using the measure tool to determine slopes of
faults is important to get a realistic understanding of the subsurface environment. The
example below shows the measure tool being used to measure the size of a
sedimentary basin to determine the cross-section area.
Results from this measurement shown right
indicate the width is almost 1500m, with a
thickness of only 20m. This results in a slope of
only 0.8 degrees! This is a good example if the
vertical exxageration commonly seen in
subbottom profiles, demonstrating the
usefulness of this measurment tool!
 Use the Measure tool to determine the cross sectional area of basins seen in
the profiles and to measure the slopes of steep surfaces and any faults
identified.
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IV. SIDESCAN PROCESSING
So far we have setup our project background and processed some subbottom profile
data. Next we will add sidescan data to our project, review the data in the waterfall
viewer, then create a mosaic from the raw sidescan data.
STEP 19: Import Raw Klein 3000 Sidescan Data Files
For this project there is only one segment of sidescan data collected with a Klein 3000
dual frequency sonar.
 Using the File menu, select Import/Raw Data File... Navigate to the
.../ LChamplain/XTF folder and select the K3000_snip.XTF file
-- Note: Importing survey data files will extract the navigation from the raw data
file, draw the navigation line in the map view, and create a cache file for storing
information from the processing steps.
The next step is to zoom into the sidescan navigation and set a region for returning to
the full extent of the sidescan data.
 To zoom into the imported data navigation lines, right-click on the
Navigation/Sidescan file tree node and select Zoom to Extents...
Before creating a region, zoom out using the 'zoom-out' toolbar button
room for the processed data to fit inside the region.
to allow
 Once satisfied with the zoom extent, press the F12 button on your keyboard to
quickly 'Add Viewport' and name this
region "Sidescan - Klein 3000"
 Right-click on the region in the file tree
and open 'Color Settings' to change the
color to green
At this point your map view should look like
the image shown right. The green line
represent sidescan survey navigation with the
arrow pointing in the direction the data was
collected.
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Before we create a mosaic from the imported sidescan data, there are three things
that should be done:
1. process navigation
2. verify/define bottom track
3. create TVG curve
STEP 20: Process navigation for imported sidescan data following these steps
Navigation processing can be performed on a single line at a time or on all lines in
the 'Navigation/Sidescan' file tree. For monitoring the affects of navigation
processing it helps to display the ping beamlines and watch how they change with
each processing step. Beamlines represent the across-track extent and heading of
each ping along the navigation line.
 First, right-click on the Navigation/Sidescan file tree node and select
Show Beamlines...
It help to use the Zoom tool
to zoom into the
navigation line and get a better view of the beam
lines.
Note that in the Pens tab of the 'Program Settings'
there are color and decimation options for the
beamlines. The default colors scheme is port=red,
starboard=green.
 Right-click on the Navigation/Sidescan file tree
node and select Process Navigation...
-- For sidescan processing, it is usually best to run
several steps with the navigation processing BoxCar filter to get uniformly
spaced and parallel beam lines.
Also, unless you have a good heading sensor in your towfish, be sure to
select CMG as the source of your heading.
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-- For more information on navigation processing options, please refer to the
navigation processing guide (Perspective_NavigationProcessing_Guide.pdf).
 In the Process Navigation dialog, click on the Filter Setup button to open the
BoxCar settings. Select:
 Window Size = 30
 Iterations = 3
 Source = Sensor
 Heading = CMG
 Speed = Off
Click OK to close the dialog and then select Start to run the BoxCar filter on the
navigation data.
Before Navigation Processing
After Navigation Processing
You will notice that for this data, the navigation processing results look good and
additional processing isn't necessary.
 Right-click on the Navigation/Sidescan file tree node and select
Show Beamlines... again to turn them off
 Click on Sidescan - Klein 3000 region to zoom out to the full extent of the
sidescan data
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STEP 21: View Waterfall and Enhance Display
To view the sidescan waterfall display either double-click on a navigation line in the
map view, or right-click on a navigation line in the Navigation/Sidescan file tree and
select 'View'. The position of the waterfall will show up in the map view along the
navigation line as shown below.
In the example above there a four channels of data displayed. This data comes from
a dual frequency sonar and therefore has two channels (port/stbd) of low frequency
and two channels of high frequency data.
Right-clicking on the waterfall and selecting Settings allows the user to choose which
channels to display and also the viewable range of each channel. It is also possible to
set the downsampling method for the waterfall view. This can be important for noisy
data like the example used in this project.
Note on waterfall downsampling: The Klein 3000 data used for this example has 3200
samples per channel, or 6400 samples per ping. Unfortunately modern monitors have a
maximum of 1920 pixels to display this data. This requires the number of samples in the raw
data to be downsampled to fit in the width of the waterfall display. To reduce the amount of
downsampling in the waterfall, stretch the window as wide as possible. Viewing only Channel
1 stretched across two 1600x1200 monitors would see all of the data without downsampling!
 Right-click on the Waterfall and select Settings...
 Change Downsample Method = Average (try other options to see affect!)
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An advantage of downsampling in the waterfall view is it can help clean up the
display of noisy data!
HISTOGRAM ADJUSTMENTS
The histogram tool allows the user to change the range of data the color map is
stretched over. By default the color map stretches over the entire data range,
however if there is high or low intensity noise in the data it can cause the image to
be washed out or too dark.
 Launch the Histogram
tool by clicking on the
toolbar button
 Set the range of value
from 5.0 to 27.0 by
dragging the slider bars
or manually entering the
values as shown in this
image:
This should both darken the image plus increase the detail seen in the data.
COLOR SETTINGS
The LUT tool allows the user to change the color map applied to the data. By
default the color map used for sidescan data is Greyscale, however there are also
three different Copper color maps plus other
options as well.
 Launch the Histogram tool by clicking on the
toolbar button
 Change the Gamma = 1.20 as shown in this
image to bring out detail in the data:
 Try different color maps, be sure to invert
the Isis and TritonMap Copper maps so that
soft = dark and hard = bright! Return to the
Greyscale color map when done
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The image below shows the evolution of imagery enhancements starting with the
default view without corrections, then with the downsampling method changed to
average, and finally with the color and histogram adjustments.
STEP 22: Verify Bottom Tracking
Bottom tracking is needed to determine the altitude of the towfish for ground range
calculations. The waterfall display of the sidescan data is used for checking bottom
tracking results prior to creating a mosaic.
In the waterfall view the bottom track shows up as a red line at the water/sediment
interface. Clicking the 'Slant Range' button
will remove the water column and
show what the data will look like in a mosaic. Below is an example demonstrating the
effects of good versus bad bottom tracking.
Good bottom tracking
Good slant range correction
Bad bottom tracking!
Bad slant range correction!!!
Water Column
Included in Slant range
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If the bottom tracking is not good, you can use the
toolbar button in the
waterfall window to open the 'Bottom Tracking Tool' for re-tracking the bottom
or for manually adjusting discrete problem areas.
 Launch the Bottom Tracking tool using the waterfall toolbar button to open
the window shown below
By default, the
Bottom Tracking
Tool window opens
displaying Channel 1,
with the entire line
compressed into the
window showing the
full along track
extent of the survey
line. Also by default,
the zoom slider on
the far right is set to
show the full across
track extent of the
data.
 Use the slider bar to zoom in the across track direction to enlarge the
water/sediment interface as shown below:
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This gives us a better view if the existing bottom track and allows us to more
accurately fix problem areas.
A few things to note about what is shown in this window.
 The red line represents the bottom track.
 The blue line represents the position that the sidescan waterfall is
currently opened at.
 The white line appears to be instrument noise and will make automatic
bottom tracking of this data very difficult!
Although the bottom track looks fairly good, to demonstrate how this tool
works we will re-track this line using the Bottom Tracking Tool.
 To automatically bottom track this line, set the following and click Compute
Please note that while
these settings work, the
level is quite low in
order to best capture
the water sediment
interface. Doing so
however will cause
other areas along the
survey line to not track
well and require manual
adjustments. For this
data, using a higher level
moves the bottom track
line into the data and
will result in position
errors in the across track
direction of any objects
seen in the mosaic.
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 Check the box for Slant Range Correct to see the results from bottom tracking
and how the line will appear if mosaiced
Note that areas where the bottom track enters the water column will have the
water column included in the mosaic! Areas where the bottom track enters the
data are not so obvious but will still result in position errors!
 Fix the problem areas by switching the Method = Manual, also uncheck the
Compress button to zoom in the along-track direction
 With the Slant Range box checked,
use the page forward arrow (below
Compress) to move through the data
stopping where the water column is
included in the data to repair the
bottom tracking
 To repair the bottom tracking,
uncheck the Slant Range box, draw a
straight line on the window and then
click along the curve to track the
bottom, see example to the right
 After the areas where the bottom
track enters the water are fixed, page through the data back to the beginning of
the line but with Slant Range unchecked to repair areas where the bottom track
enters the data
Note 1: To see effects of bottom track changes applied to the slant range, you
must click the Apply button!
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Note 2: The other important option in the Bottom Tracking Tool is the ability to
update the XTF file with the new bottom tracking information. In general, bottom
tracking changes are written into the cache files, however cache files are not
permanent. After spending time to properly bottom track data, it is reassuring that
this new bottom track can be written into the XTF files. This is the only place in
Perspective where the user is allowed to overwrite their raw data!
 Click the Close button on the Bottom Tracking Tool window when finished
 Back in the waterfall window, apply Slant Range and scroll through the data
to see results
The image below shows the waterfall with the new bottom tracking applied:
STEP 23: Create TVG Curve
In the image above we can see the good slant range corrected waterfall still has a
dark line down the center of the low frequency data, with the high frequency data
showing a thinner black stripe at nadir with a bright zone in the near nadir area. To
correct for these changes in signal gain we can apply a Time-Varying Gain (TVG) to
the waterfall.
The TVG tool is launched from the waterfall
window by clicking on either
the manual
or
the automatic TVG toolbar buttons.
Using the automated option creates a
separate curve per channel of data!
 To create a TVG curve to use during
processing, select the AutoTVG toolbar
button
 Use the default settings and click Generate Curves
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This creates the following four TVG curves and changes the waterfall appearance as
shown below:
Note that the curves for CH1 & CH3 were reversed so they match the sidescan record
below with the nadir in the middle!
Looking at the corrected sidescan waterfall we can still see some TVG artifacts in
both the low and high frequency data. However by clicking on the star-shaped nodes
in the TVG curve window the user can manually adjust the automated results.
 Adjust the TVG curves to lighten the nadir stripe and remove dark band near the
max range for CH 4
Shown below are the manually revised TVG curves for each channel with the
resulting changes to the waterfall:
When satisfied with the TVG results, make sure to save the TVG curve before closing
the TVG window.
 Click the 'Save TVG Settings' button, name the file "K3000" and save the file to
C:\TritonDemos\LChamplain\TVG
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Note that depending upon where along the survey line you choose to create your
TVG curves, they may look slightly different from the ones in this guide!
Now that the navigation is processed, the bottom track is properly set and a TVG
curve has been created for each channel, we are ready to create mosaics from the
sidescan data.
STEP 24: Create Mosaic - High Frequency Channels
Now that the navigation is processed, the bottom track is properly set and a TVG
curve has been created for each channel, we are ready to create mosaics from the
sidescan data.
 Create a sidescan mosaic by clicking the toolbar 'Create Mosaic' button
main Perspective map window
in the
-- Mosaic Wizard - Page 1: CHOOSE/CREATE MOSAIC LAYER
o Click on 'Create' to enter a file name and to select a location to save the
mosaic file. Call the file "K3000_455k_ pt2m" and place the file in
C:\TritonDemos\LChamplain\MOS
o Select 'All lines in one Mosaic' and click 'Next'
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-- Mosaic Wizard - Page 2: CHOOSE MOSAIC SETTINGS
o use settings shown above and click 'Next'
-- Mosaic Wizard - Page 3: SELECT/ORDER INPUT LINES
o check the box for the survey line and click 'Next'
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-- Mosaic Wizard - Page 4: GEOMETRY SETTINGS
o use settings shown above and click 'Next'
-- Mosaic Wizard - Page 5: LINE AND CHANNEL SETTINGS
o use settings above, be sure the select Port = 3, Stbd = 4, and click 'Next'
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-- Mosaic Wizard - Page 6: GEOMETRY SETTINGS
o use settings shown above
o be sure to load the TVG curve created!
o click 'Finish' to create the mosaic
Once the mosaic is created it will automatically load into
the project and will appear like the image shown right
STEP 24: Create Mosaic - Low Frequency Channels
Next we need to create another mosaic, but this time using the low frequency
channels.
 Create a sidescan mosaic by clicking the toolbar 'Create Mosaic' button
main Perspective map window
in the
o Call the file "K3000_100k_ pt2m
o keep all the same settings except select Port = 1, Stbd = 2 in the Line and
Channel Settings (page 5)
o click 'Finish' to create the mosaic
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 Before continuing, zoom into each mosaic and verify
that the bottom tracking was good throughout the
entire line and that the TVG curve did an adequate job
removing gain artifacts.
When sidescan mosaics are created, they automatically load
into Perspective and appear in the Imagery file tree as
shown to the right.
STEP 25: Review Results
Perspective has a great tool for comparing overlapping data which can be used here
for reviewing each mosaic as well as comparing the results. Individual grids and
mosaics can be opened in a separate map window with the map scale, extent and
cursor position synced.
 Right-click on the 'K3000_100k_pt2m' mosaic and select 'Open Map View'
 Repeat for the 'K3000_455k_pt2m' mosaic
The example below shows the two Open Map View windows with the map scale
synced so when zooming in one, it will zoom in the other as well. Note the locked
cursor position which allows for a specific location to be compared.
Note, when creating high quality mosaics, it is best to playback every line from start to
end to verify bottom tracking is good and that the TVG curve works well. For surveys
with large gain changes between lines it may be best to make a TVG curve for each line
and create a separate mosaic for each line to preserve their individual dynamic range...
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V. DATA FUSION
Now that there is both processed sidescan and subbottom data in the project, the
user can take advantage of the data fusion capability of Perspective linking the
same location in the map window, the sidescan waterfall and in the subbottom
profiles as shown in the example below.
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VI. EXPORTING/FINAL PRODUCTS
There are many formats for saving and exporting data in Perspective. Listed
below are different export options available from this project.
STEP 26: Try the export options you are interested in...
MAP VIEW EXPORTS
 GeoTiff:
Includes everything turned on
 KML:
in the file tree to the extent
 IMAGE:
of the map view
SUBBOTTOM PROFILE EXPORTS
 SEGY:
create new SEGY file with processed navigation
 TIFF:
export to vertical Tiff, includes information text file
 SD:
save profile directly to SD file for viewing in Fledermaus in 3D
SUBBOTTOM REFLECTOR EXPORTS
 CSV:
output reflector nodes to text files
output thicknesses between defined reflectors
SIDESCAN EXPORTS
 GeoTiff: Mosaics and Targets
 KML:
Mosaics
 XYA:
Mosaics
NAVIGATION EXPORTS
 DXF:
Polyline DXF files of navigation lines
 CSV:
Text export for each navigation update
We provide Global Mapper for customers needing Smooth Sheets, and SevenCs
software for creating ENC and paper charts.
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