How to Use Pocket DLog

How to Use Pocket DLog
This is a tutorial discussion of the operation of a piece of software. In creating
this document, we have made certain assumptions about you:
1. You are familiar with the operation of your handheld device and your GPS
receiver.
2. You have some familiarity with the Pocket PC operating system.
3. You can operate Microsoft’s ActiveSync utility for transferring data and
files between your desktop computer and your handheld device.
4. You have some experience with mapping or GIS systems.
Consult all relevant documentation for background and detail on these topics if
you need a refresher. Topics relating to these areas are mentioned in passing if
at all in this document.
What does DLog do?
You use DLog to digitally map the outlines of area features (the boundary of a
farm field), the runs of linear features (an irrigation ditch) or the positions of point
features (a soil sample point) on the landscape. “Mapping” involves an
organized collection of coordinates into distinct features.
Coordinates
We all know this stuff at some level but a very basic review doesn’t hurt:
In two dimensional space, what we stand on, coordinates are numbers that
locate a position in terms of the distance to the right (east) or left (west) of an
origin and the distance above (north) or below (south) of the same origin.
The origin, the distance units and the orientation of the x- and y-axes define a
‘coordinate system’. The coordinate source that DLog uses in digitizing is GPS.
The GPS coordinate system is ‘geodetic’. Geodetic coordinates are latitude and
longitude expressed in angular units, most often as degrees, minutes and
seconds.
You may be familiar with other coordinate systems in which x and y are given in
linear units, feet or meters, instead of longitudes and latitudes. There are
coordinate transformation formulas that allow us to move between geodetic and
plane coordinate systems.
Geodetic coordinates locate positions on the earth in two dimensions relative to
an origin that is the intersection of the 0 degree meridian (line of longitude) and
the 0 degree parallel (line of latitude). You may have heard these lines called
Prime Meridian and Equator respectively.
Geodetic coordinates give us the unique geographic address of an event (e.g.
the place where your soil tested at 6.1 pH) or thing (an irrigation outlet) on the
surface of the earth.
Features (also referred to as Objects)
An ordered collection of these geographic addresses can be used to represent
almost anything on a map sheet. We’ll use “x” to symbolize longitude and “y” to
symbolize latitude. “x1,y1” is shorthand for the first coordinate pair in a
sequence, “x2,y2” is shorthand for the second coordinate pair in a sequence and
so on. In any coordinate system, “X” is used to denote movement left or right
(east or west) and “Y” is used to denote positions up or down (north and south).
1. A single coordinate pair, x1, y1, would be a point. It denotes a feature
with no length and no area. The example would be a soil sample point.
2. Two coordinate pairs, x1,y1 – x2,y2, where the locations of x1,y1 and
x2,y2 are not equal would be a straight line. It denotes a feature with
position and length but no area. The example would be a perfectly
straight irrigation ditch.
3. A sequence of coordinate pairs, x1,y1 – x2,y2 - …… - x8,y8, where the
locations of x1,y1 and x8,y8 are not equal would be a linear feature with
some shape as defined by the intervening coordinate pairs. It denotes a
feature with position and length but no area. The example would be a
winding stream channel.
4. A sequence of coordinate pairs, x1,y1 – x2,y2 - …… - x8, y8, where the
locations of x1,y1 and x8,y8 are equal would be an area feature (a
polygon). It denotes a feature with position, length (perimeter) and area.
The example would be the border of a farm field.
So, GPS is the coordinate source and DLog is the software that manages the
collection of coordinates into features that will mean something to you and others
when they are viewed as a map.
Connections
DLog is software. It was designed to run on handheld computers under
Microsoft’s Pocket PC operating system.
To digitally map, the handheld device must be connected to a GPS receiver.
When we refer to a GPS receiver, we are talking about products from people like
Garmin, Trimble, CSI, Novatel and others. The fact is that any receiver capable
of NMEA (National Marine Electronics Association) output can be used. There
are significant performance differences between receivers but the fundamentals
are the same.
The mapping system we are talking about has the following:
1.
2.
3.
4.
GPS receiver and antenna.
Serial cable that connects GPS receiver and Handheld device.
Handheld device.
DLog software loaded on the Handheld device.
The assumption is that you have or your dealer has assembled these
components and all are in place and working.
Starting the Program
In succession, tap Start | Programs | Pocket DLog
This brings up the DLog interface. Everything is blank or low-lit (inactive)
because this is the first use of DLog. As you build projects and their layer
content, DLog will display the last project/layer structure you were working in
when you quit DLog.
Setting Operating Properties
Tap File | Properties…
Before you start working with DLog you have to do some setup. Typically, unless
you change GPS receivers or you want to change certain graphic characteristics,
you only set properties once.
Most critical is telling DLog how it will communicate with the GPS receiver.
Port - In most configurations you will be connecting to the GPS receiver through
the first serial port of your Handheld device. The default Port setting, “COM1” will
be correct in most cases. If you have a GPS receiver with a CF Serial I/O
connector, you could connect through the second serial port on your Handheld
device. In this case you will have to consult your Handheld device supplier to get
the correct COM port (it is not necessarily COM2).
Baud – This is the speed of the transfer from GPS receiver to Handheld device.
The baud rate you select must match the baud rate of the GPS receiver. Many
receivers have selectable output baud rates. Consult your GPS manual on how
to set baud rate and what settings are possible. The default rate for many
receivers is 4800 baud.
Type – There are three choices: 1) NMEA which is the default. 2) Geotracer
which refers to a specific product of Trimble/Spectra Precision (please contact
this group for information on Geotracer) and 3) RTK NMEA which refers to high
accuracy systems made by Trimble and others. The choices refer to the format
of the messages being output by the GPS receiver. DLog only accepts NMEA
and all three choices are ultimately NMEA. Please note that not every GPS
receiver puts out NMEA by default. Some require a deliberate setting to “NMEA
output”. Consult your owner’s manual on how to do this if necessary. Also note
that not every receiver puts out the same set of NMEA messages nor does every
receiver put out the current version of NMEA.
If you have problems with DLog, the first thing to consider is whether these
communication settings have been made correctly and if your GPS receiver is
putting out NMEA strings in the required format. (DLog can work from a single
$GGA or it can accept a series of non-proprietary strings. You must check with
your GPS supplier to make sure that the GPS receiver is capable of standard
NMEA v2.25 or v2.3 output.)
The remaining settings are optional:
Background Color – Select either a black or white background for digitizing by
tapping the appropriate radio button.
Icon Type - Select either a tractor or triangle (default) for the icon used to mark
your current position as you digitize. The middle of either icon is your current
position.
Closed Object Fill – If you digitize area objects such as farm field boundaries,
ponds, weed patches, etc., do you want these to be shown on your Handheld
device’s screen filled in with color? If you do, tap the drop down arrow and select
Solid Color otherwise only the perimeters of the objects you are digitizing will be
displayed.
Moving Map Mode- The Expand selection will continuously expand (minimize)
the display as you travel off the edge of the current view extents during digitizing.
The Fixed selection will maintain the current view extents, updating the view as
you travel at a fixed expansion factor.
Dwell Point Capture - A ‘dwell point’ is a type of feature you can collect by
sitting still at a location. The theory of a ‘dwell point’ is that by taking the average
of coordinates collected over time, the accuracy of your position can be
improved.
You might use the dwell point function to ‘survey in’ a permanent marker or
benchmark for other GPS activities. You can set the number of collections for
dwell points from 1 to 10,000. The default value is 300 collections.
The time involved is a function of your GPS receiver’s collection rate. Many GPS
receivers collect at a fixed frequency, 1 point per second, and some allow you to
set collection rates. If you were using a Trimble Ag132 at a 5Hz collection rate, a
dwell point setting of 300 would take 60 seconds to complete a single point. If
the Ag132 setting is 1Hz, a dwell point setting of 300 will take 5 minutes to
complete.
Speed Filter- At slow speeds, GPS position can be very erratic. The behavior at
low speeds (typically below 3mph) will vary from receiver to receiver. If you want
to exclude points that are collected below a certain speed, enter a value here.
Points Missed Warning – GPS With the selection On (default): If you lose
GPS signal, the device screen will flash in reverse video mode to alert you and a
“Lost GPS” message will appear. No points will be collected during a brief loss of
GPS.
With the selection Off: No warning will be issued.
Please note that these selections are designed for intermittent signal losses. If
the unit becomes disconnected from the GPS or if GPS signal loss persists, you
will receive a different message, “GPS device has timed out…”.
In either case, the significance is that coordinate collection is interrupted. You
will have to make a spot determination as to whether or not the collection losses
are significant. There are times when you may have to re-collect the feature
once you have determined the cause of GPS signal loss.
Points Missed Warning – Differential GPS digitizing operations use GPS
receivers that are capable of differential correction.
Differential correction signal is in addition to GPS signal. You can be receiving
GPS signal but not be receiving differential correction. Is this a condition you are
willing to accept?
With the selection On: If you lose differential correction, the device screen will
flash in reverse video mode to alert you and a “Lost Differential” message will
appear. No coordinate collection will be made with differential lost.
With the selection Off (default): No warning will be given and coordinate
collection will continue (if GPS signal is maintained).
IN THE CASE OF RTK NMEA…
If your choice of collection type is RTK NMEA a loss of RTK correction will ignore
coordinates until RTK is restored.
If you lose RTK correction, the device screen will flash in reverse video mode to
alert you and a “Lost RTK” or “Insufficient satellites” message will appear.
Display Units- Linear units can be set to feet or yards depending on your
preference. This will affect the display in Pivot Point and interactive
measurement operations.
When you are finished setting properties tap OK. If you tap X (cancel), the
property settings will not be saved.
The Organization of Work
Basic Rules:
1. The work you do with DLog is organized by Project and Layer.
Digitizing is undertaken By-Layer in the context of a project. You
must create a Project before you can define layers and you must
create at least one layer before you can begin digitizing.
2. A Project can contain up to 32 layers or a combination of layers and
background drawings or images that total 32.
3. A layer can contain any number of features so long as every
feature is the same type. This means that a layer containing area
features cannot also contain point features; a layer containing line
features cannot contain point or area features.
4. The types of layer features are: Area, Line and Point with special
versions of each.
5. While all DLog activity is visible on your Handheld device, all DLog
activity must be transferred from your Handheld device to your
desktop through a reformatting process before the collections can
be used in a mapping or GIS application.
Let’s put these rules in a real world context.
You are a crop consultant and you have a client, Mr. Smith, who has contracted
you to go on his farm to 1) map a field boundary 2) map weed patches and
3) Mark and take soil samples. The workflow goes like this for Mr. Smith:
1.
2.
3.
4.
Create a project titled “Smith Farms”
Create a layer under Smith Farms titled “Fields” as an ‘area’ layer.
Create a layer under Smith Farms titled “Weeds” as an ‘area’ layer.
Create a sample layer under Smith Farms titled “Soils” as a ‘point’ or
‘sample point’ layer.
5. Select layer “Fields” and drive the perimeter Smith’s field.
6. Select layer “Weeds” and drive the perimeters of weed areas in Smith’s
field.
7. Select layer “Soils” and collect points at each location where a sample is
taken.
8. Back at your office, move the collections under project “Smith Farms” from
your Handheld device to your desktop and bring them into your mapping
or GIS system which could be AGIS, ArcView, MapInfo or Autocad.
9. Prepare maps of your activity for Mr. Smith.
It is that straightforward. The rest of this document gives you the details of how
to do this.
Creating a project.
There are two conditions for project creation:
1) Working Offline (without connection to GPS) and
2) Working on line with the GPS connected and transmitting good
coordinates.
Unless you are comfortable with accurately noting and entering coordinates in
latitude and longitude we recommend that you create projects with GPS
connected (condition 2).
If you are comfortable with project location entry, you can create projects and
layers in your office, working ‘offline’, so that you are set up and ready to go
when you hit the field.
Project Creation Offline.
You would do this only if you know the location of intended activity to
approximately one minute of latitude and longitude. Many users can put their
hands on this information from prior use of their GPS receiver or by picking a
coordinate from their mapping or GIS systems.
Step 1. Tap File | New Project…
Step 2. Supply the latitude and longitude coordinates for this project by tapping
the values on the Handheld device’s keypad. Set the hemisphere for the latitude
as north or south from the drop down. Set the hemisphere for the longitude as
east or west. The entries below are for a project is in SW Louisiana, north of the
equator and west of Greenwich. Of course, you would supply coordinates that
are local to your area of operation. Tap OK to proceed to the next step.
Step 3. Supply the name of the project by tapping the characters on the
Handheld device’s keypad.
You see that this project is named ‘New Iberia’. The coordinates you supplied as
the approximate center of project activity are shown along with the corresponding
UTM Zone 15. Tap OK to complete the project set up.
Some Discussion: What is the concern with ‘UTM Zone’? What is that
anyway? Well without going into a lengthy discussion, the quick answer is that
DLog works in map projected space. The map projection being used is Universal
Transverse Mercator. The issue turns on putting something round (geodetic
coordinates) on something flat (a display screen or map sheet). To do this you
need a projection from one coordinate system to another. Since we are
ultimately concerned with making a map we use a map projection. In every case
DLog will figure out the appropriate UTM Zone for you. The details of map
projection are not your concern until and unless you are distributing your work to
a mapping system or GIS. Even then you are taken care of in most systems.
At this point your project is established.
Project Creation Online
The scenario is this: You are in the field. GPS receiver is connected to
Handheld device. Power is on for both devices.
Before creating a project online, you need to verify that GPS signal is being
received and that GPS coordinates are correct.
Step 1. Start DLog Start | Programs | Pocket DLog
Step 2. Tap File and note the Work Offline drop down menu item. It should be
checked, indicating that your Handheld device is not “listening” to the GPS
receiver. Note that the menu item, “GPS Status…” is low-lit to show inactivity.
Step 3. Tap the Work Offline menu item to uncheck it. Now you are online to
the GPS receiver. Note that the menu item, “GPS Status…” has changed to an
active state.
Step 4. Tap GPS Status… and a GPS Status dialog appears.
If this dialog does not appear, it means that you have a communication problem
with the GPS receiver. Check the connection between GPS receiver and
Handheld device. Check the settings under File | Properties… to make sure
that COM port and baud rate are correct.
Information elements in this list are local time, latitude, longitude, altitude, speed,
heading, differential, HDOP, satellites, differential age, differential source. All are
reported relative to your current position. In viewing this dialog ask yourself the
following:
1) is the time right?
2) are the latitude and longitude coordinates correct?
3) if you expect to be using differential correction, is the report showing
“Differential GPS Fix”?
If these appear to be correct, you have a good GPS signal and you can proceed.
If they do not appear correct, wait for half a minute or so to see if the report
corrects itself. If not, check your surroundings.
1) Are you near any source of electrical interference?
2) Are you beside or under any obstruction of the GPS antenna’s line of
sight?
If you think you have an interference or line of sight problem, move and keep
checking the report. It should correct itself. Sometimes you simply can’t operate
in the current surroundings- local interference defeats the receiver, you can’t get
a good line of sight for the GPS antenna or you are too far away from a source of
differential correction.
The point is: Do not try to create a new project until the GPS Status report is
giving correct numbers. If you proceed in the face of an incorrect or inconsistent
position report, the collected data will be degenerate and your mapping project
will fail.
With a correct and stable position report, proceed with new project creation by
tapping OK on the GPS Status dialog. Then tap File | New Project… and
supply a name for the new project as you did in Step 3 of Project Creation
Offline.
When you have finished supplying a new project name and you have tapped the
OK button, you will see the position icon displayed in the center of the Handheld
device’s display screen. This indicates that you are communicating with the GPS
receiver. You are ready at that point to define layers and begin digitizing.
Summary of Project Creation
1. All work in DLog is organized under projects.
2. DLog projects can be created “offline” without connection to a GPS
receiver or “online” with connection to a GPS receiver.
3. In either case, a name and a project origin point, given as latitude
and longitude, define a project. The origin point must be near the
actual area of operations (within a mile). If you supply an origin
point incorrectly (working offline) or if an origin is collected from the
GPS receiver (working online) before the GPS receiver has
initialized, your mapping efforts will be based on degenerate
coordinates and they will fail to produce good results.
4. Reasonable attention and care in project creation do not take time
or sophisticated understanding of GPS and maps. But, reasonable
attention and care must be given.
5. Once a project has been successfully created you can open it and
add to it at any time. You do not have to recreate a project each
time you want to work in it.
Layer Creation
Back to our earlier scenario, grower Smith has contracted you to map a field,
take soil samples and map any large areas of weed pressure. You just created a
new project titled “Smith Farm”. Now you are going to create the layers that will
organize and receive coordinate inputs under this project.
You have answered “whom” you are creating maps for. In creating any layer,
you have to think about the following:
1) What am I going to map? In this case, a) Field Border b) weed areas and
c) sample sites.
2) Do the things or events to be mapped fall into separate classes? In this
case, definitely: borders, weeds and sample sites.
3) When I digitize a feature in each class, what object type makes sense in
collection/visualization? In this case, borders and weed areas are closed
polygons (area types) and sample sites are points.
4) When I complete the digitizing of a feature, what do I want to say about
the feature that would be a useful description to another person? What
we are talking about here is “feature attribution”- associating some
meaningful descriptors with each feature as it is digitized.
You can create layers ‘online’ or ‘offline’. Our suggestion is that you will probably
find working ‘offline’ less distracting.
Create the layer for “Field Borders”
Step 1. Tap Layer | New… to pop up the layer creation dialog.
Step 2. Supply a name for the new layer by tapping in the Layer Name edit box
and then tapping on the keyboard icon to activate the Handheld device’s
keypad. Tap the name as “Border”. Tap on the keyboard icon again to put the
keyboard back.
Step 3. Define attributes.
Some Discussion on ‘Attributes’:
The default state for layer creation is “No Attribution”, meaning that no attributes
will be associated with features created in the layer.
In some cases the “No Attribution” state can make sense. If you are only
interested in mapping the run of irrigation ditches without making any comments
about the condition of the ditch, its width or any other descriptor, you might
consider the name of the layer, “Ditches”, to be an adequate description of each
and every feature in the layer.
However, in the case of Mr. Smith’s field(s) you want to describe the feature(s)
being digitized under “Border” by supplying a farm field name, e.g. “Dad’s 80”.
You could have additional attributes (up to a total of 32) that would enhance the
description of a farm field beyond its name. Examples could be “crop planted”,
“ownership”, “tillage method”, etc. In our case the farm field name will be the
only attribute.
To continue with setting up the layer…
1) Tap the No Attribution check box to remove the check mark. The state is
now active and you can define the table field(s) that will hold attributes.
2) Tap in the Attribute Name edit box and tap the keyboard icon. Supply
the title of the attribute as “Field ID” by tapping on the keyboard. Then,
tap the keyboard icon again to put it back.
3) Leave the Type drop down list entry set to Char. This means that your
attribute entries in this table field will always be “character” as opposed to
“numeric” – words instead of numbers.
4) Tap in the Size edit box and tap the keyboard icon. Supply a table field
length of “12” by tapping on the keyboard. By supplying a length of 12,
you have said that any name entered as an attribute must be twelve
characters or less in length. Then, tap the keyboard icon again to put it
back.
5) Tap the Area radio button. This defines the feature type for this layer as
exclusively limited to area features. You cannot digitize a point or a line
object in this layer.
6) Finally, put your stylus on the horizontal scroll tool next to the color chip.
Moving the scroll tool right and left will change the color of the chip. This
is how you specify the color in which features that you digitize under this
layer will be displayed. If you slide about a quarter length to the right, the
color should be orange. Your New Layer dialog should look like this:
A little more discussion on layer creation and attributes:
You have created a layer under project “Smith” that is titled “Border”. It will
contain area features only. It has an attribute opportunity to supply a single
descriptor to a character table field titled “FIELD ID”. The longest name you can
use is twelve characters. This means that “Dad’s 80” is legal length but “Nathan
Bedford Forrest Memorial Corn Field” is not.
If you have had any exposure to a database program such as dBase or Microsoft
Access, you probably see that you are creating a table structure. Layer creation
mixes graphic and database operations.
7) Tap OK on the new layer dialog to complete the creation of this new layer.
Now your Project/Layer drop down lists look like this:
The Project is “Smith”. The first layer under this project is “Border”. “Border” was
created to receive digitizing activity related to farm field boundaries. The
“Border” layer could contain one or hundreds of features depending on how
many farm fields Mr. Smith wants mapped.
Digitizing the Boundary of a field on Smith’s Farm
Digitizing only happens with the GPS connected and with DLog set to work
‘online’.
Remember, ‘offline’ is this state:
‘Online’ is this state:
When you are ‘online’ you will see the digitizing icon in the middle of the
Handheld device’s display and you will see the first button on the “go-pause-stop”
button bar lit green.
If you do not see this and you have established that the state is ‘online’, tap File |
GPS Status and wait half a minute or so to see if the GPS status corrects itself.
If GPS status is not available, you have:
1) a communication problem between GPS and Handheld device
2) an environmental problem like line-of-sight obstruction or electrical
interference
3) a failure of one or both devices or some combination of these three
possibilities.
To digitize our hypothetical field is going to take some imagination. Imagine that
you position yourself at the southeast corner of Smith’s field. You are going to
drive the perimeter of this field. When you are ready to go (heading west and
then north in your imagination):
Step 1. Tap the green button to start digitizing (remember that digitizing means
making an ordered collection of coordinates). As you move, the position of the
icon follows your line of travel and a “bread-crumb” trail marks where you have
been. You also note that the “go-pause-stop” button bar has changed state. The
green button is now low-lit and the second and third buttons are yellow (pause)
and red (stop) respectively.
Step 2. Just before you make the circuit of the field, when you are a few feet
from your starting point, tap the red button to stop digitizing. Because you
declared all objects in the ‘Border’ layer to be areas, tapping the red button stops
collection and forces closure from the stop point to the start point. You will see
the breadcrumb trail change from ‘dots’ to a solid line.
Note this: If at any time during your circuit of the field it becomes necessary to
pause operation (you need to drive around an obstacle), tap the yellow button to
pause. Collection will stop until you hit the pause button again. So the sequence
is, tap pause-reposition yourself to a resume point-tap pause again to resume
collection.
Step 3. Supply an attribute describing the feature. When you created the
‘Border’ layer you set up a single attribute field titled ‘FIELD ID’. Now it is time to
supply the name of the field you have just digitized.
1)
2)
3)
4)
5)
Tap in the edit box next to FIELD ID.
Tap the keyboard icon.
Tap the name of the field (we called it “Dad’s”)
Tap the keyboard icon to put away the keyboard.
Tap OK to save the entry and continue.
With the operating state ‘online’ you could continue to digitize the perimeters of
any number of fields under the ‘Border’ layer by repeating these three steps.
Building the next layer- Weeds
Another Approach to Attribution: Using the Data Dictionary
You just saw how a layer is created with an attribution opportunity that allows for
free-form entry. There are situations in which you may want to develop a fixed
structure of attributes to avoid typing and the inevitable mistakes that come with
keyboard entry. The mechanism for this is DLog’s Data Dictionary. We will
demonstrate its use with the next layer for the Smith Farm project- Weeds.
Data Dictionary construction can be done ‘offline’ or ‘online’. The Data Dictionary
can be edited or appended at any point and the Data Dictionary is ‘global’meaning it is available for use with any project.
Step 1. Tap File | Data Dictionary… or tap the
will pop up the Data Dictionary dialog.
icon on the toolbar. This
Let’s say that it makes sense to make two observations about weeds: ‘Weed
Class’ and ‘Weed Pressure’. You want to be sure that the same descriptors are
used in any weed scouting activity whether it is for Smith or any other client.
For ‘Weed Class’ you want one of three attributes to be consistently applied
when a scout digitizes a weed patch in Smith’s field:
a) Broadleaf
b) Nettle
c) Mixed.
For ‘Weed Pressure’ you want the attributes to be a) dense, b) moderate or c)
sparse.
Build the first field, ‘Weed Class’, and its content:
Step 2. Tap in the edit box next to the Add button under the Field Names: drop
down.
Step 3. Tap the keyboard icon to bring up the keyboard and type ‘Weed Class’.
Step 4. Tap the Add button to add ‘Weed Class’ to the Field Names: drop down
list.
Step 5. Tap in the edit box next to the Add button under the Values: list.
Step 6. Type ‘Broadleaf’.
Step 7. Tap the Add button to add ‘Broadleaf’ as the first of three weed classes
to the list.
Repeat steps 5, 6 and 7 to add ‘Mixed’ and ‘Nettle’ to the list.
Build the second field, ‘Pressure’ and its content:
Repeat steps 2, 3 and 4 to add ‘Pressure’ to the Field Names: drop down list.
Repeat steps 5, 6 and 7 to add ‘Dense’, ‘Moderate’ and ‘Sparse’ as content for
the table field.
Step 8. Tap the keyboard icon to put the keyboard away.
Step 9. Tap X on the Data Dictionary dialog to conclude and save the work.
Now these entries are available for feature attribution.
To edit the Data Dictionary at any time:
Tap File | Data Dictionary… or tap the
up the Data Dictionary dialog.
icon on the toolbar. This will pop
Delete a fieldStep 1. Select the Field Name to be deleted from the drop down list and tap the
Delete button.
Delete the content of a fieldStep 1. Select the Field Name to be deleted from the drop down list and tap the
Delete button associated with the Field Names: area.
Step 2. Tap a list entry to highlight it. Tap the Delete button associated with the
Values: area.
Summary and Data Dictionary Rules:
1.
2.
3.
4.
Data Dictionary construction and editing can be done ‘online’ or ‘offline’.
Any number of table fields can be specified.
Any number of content list entries can be created under a table field.
Five is the maximum number of table fields that can be used in feature
attribution.
5. We suggest that you use the Data Dictionary only for attribution of those
features that have consistent attributes. A data dictionary of farm field
names would only work if you were in possession of a list of all possible
field names in your area of operation- that could be hard to manage.
Sometimes you have to work free form.
Layer Construction with the Data Dictionary
Step 1. Tap Layer | New… to pop up the New Layer dialog.
Step 2. Supply the name of the new layer as ‘Weeds’.
Step 3. Uncheck the No Attribution check box.
Step 4. Tap the drop down arrow under the Attribute Name column and select
‘Weed Class’ from the list of available table field names.
Step 5. Tap the New button under the Attribute Name column.
Step 6. Tap the drop down arrow under the Attribute Name column and select
‘Pressure’ from the list of available table field names.
Step 7. Confirm that the Area radio button is active.
Step 8. Select a color that is different from that chosen for features in the first
layer, ‘Border’. This is optional but it helps to have features color coded ‘bylayer’.
Step 9. Tap OK to save this layer specification.
Digitize Weed Areas
You would do this ‘online’ using exactly the same procedure that you followed in
digitizing the farm field boundary under layer ‘Border’. The difference appears at
the point of feature attribution.
Step 1. Tap the drop down arrow on the middle drop down list to select ‘Weeds’
as the active layer.
Step 2. Locate the first area of weed pressure to be mapped in the field and
position yourself at a start point along its boundary. Tap the green button to start
digitizing.
Step 3. When your circuit of the weed patch has nearly completed (within a few
feet of your starting position), tap the red button to close and conclude the
feature. This will pop up the attribution dialog.
Step 4. Because a data dictionary has been created, the attribution of this
feature is slightly different. Use the drop downs to select attributes as stored in
the data dictionary. In this instance you observed a large area (4.724… acres) of
“broadleaf weeds with the potential to exert moderate pressure on the crop”
Step 5. Tap OK to save this attribute association with the feature you digitized.
Again, you could repeat steps 2, 3, 4 and 5, as many times as there are separate
weed areas to be mapped in Smith’s field. All would be associated with the
‘Weeds’ layer. All would be closed areas. All would have attributes selected
from the data dictionary lists.
A new layer type for soil sampling
Finishing the work for Smith requires a new layer type called Sample. Layers of
this type are listed in the third drop down list box.
To create the sample points layer:
Step 1. Tap Sample | New…
Step 2. Supply a name for the layer.
Step 3. Select the bitmap symbol used in plotting points by sliding the selection
bar.
Step 4. Tap OK. There are no attributes associated with sample features other
than the sequence of their collection.
Mapping sample sites using a grid.
The features being digitized for this layer are points. The positioning of these
points is made relative to a regularly dimensioned grid overlay.
How to make a grid overlay (Basic Interactive Method)
Step 1. With the border in view, tap File | View | Grid…
Step 2. Supply spacing for the grid overlay by tapping in the X-Spacing and YSpacing and typing a value for each grid division. In this case, the grids are
going to be squares 100 by 100 feet. Tap the On radio button followed by OK.
This will put you back to the main display where you will define the height, width
and angle of the grid.
Note This: The units in this example are Feet. If you want to work in metric
units you must make this selection through the Pocket PC operating system at
Start | Settings | Regional Settings on the Number tab, item Measurement
System. Pocket DLog must be shut down before you make a change in
measurement units.
Step 3. Using the stylus:
a) draw the first edge of the grid. This can be horizontal or vertical. The
length of this line will determine the width or height of the grid. The angle
at which you draw this line will determine the rotation of the entire grid.
b) Lift the stylus off the main display. Put the stylus back on the main display
and draw the second edge of the grid. This line will start are the end of
the previous line and the connection will perpendicular. The length of this
line will determine the remaining dimension of the grid. Obviously, it
makes sense to draw the grid relative to an existing feature such as the
boundary of the field you are sampling.
When you lift the stylus off the display after completing the second line. The grid
is displayed.
If you make a mistake in defining the grid, repeat Step 1 and redraw.
How to make a grid overlay (Parameter Input Method)
There are cases, such as in a topo survey layout, in which it may be useful to
build a grid based on your current position.
You can say that your position is the point from which you want a grid to plot to
the right and left (west and east) and up and back (north and south). You can
also define the angle of the grid as its rotation about your current location
(clockwise from 0 North through 360 degrees).
This option is only available to you in the field with your device connected to
GPS.
Step 1. Tap File | View | Grid
Step 2. Supply grid spacing dimensions for X-Spacing and Y-spacing
Step 3. Tap the On button.
Step 4. Check the “Use GPS Position” box.
Step 5. Supply values for grid extents to the west, east, north and south of you
current position and supply an angle of rotation for the finished grid.
(Consider this case: You are at the southwest corner of a field that is 1000 feet
north to south and 800 feet east. You set X and Y spacing at 100 feet. The
parameters you supply are 1000 feet north, 0 feet south, 800 feet east and 0 feet
west. The angle is 0 because the field is perfectly oriented north to south. The
result will be a grid that fills the field to the north and east of your current
position.)
Step 6. Tap OK on the Grid Parameters dialog to return to general DLog
operation and plot the grid as specified.
Note: Tapping the “x” control aborts the Grid Parameter setting and returns to
general DLog operation with no parameters saved.
Digitizing features in the Sample layer
The grid overlay on the field was built as a guide to sampling. You want to
navigate to the center of each grid cell that is inside the field boundary and mark
the location from which a soil sample is taken.
Step 1. When you reach a point and collect a sample tap the ‘bull’s-eye’ (fourth
button) on the go-pause-stop button bar.
Each time you tap the bull’s-eye, a point is digitized. No attribution is required. A
sequence number is displayed as each point is digitized. You would continue
this process until all sample points have been digitized.
Summarizing to this point
1. You have seen how to create a project. Typically a project answers the
question: whom am I doing this work for? You can have any number of
projects. A project is a permanent workspace unless you delete it. Two
months from now, Smith could ask us to digitize drainage ditches on his
farm. All we would need to do is:
a) select the ‘Smith’ project
b) create a new layer titled ditches
c) digitally map those features.
2. You have seen how layers are created. A single project can have up to 32
layers. A layer can contain any number of features. A layer is a
permanent workspace within a project unless you delete it. Smith could
ask us to come back and map the rest of his fields next year. All we would
need to do is:
a) select the ‘Smith’ project
b) select layer ‘Border’ as the active layer
c) digitally map additional features.
You would not create a new layer in which to collect additional field boundaries
for Smith.
3. You have seen that features in layers can be attributed in a free-form
manner, through the use of a predetermined attribute structure or not at
all. However, the choice you make for an attribution strategy is fixed. We
could not go out to Smith’s place and add additional field borders to the
‘Border’ layer without attribution.
4. You have seen that there is a specific type of layer that relates to points
only called a Sample layer. It is created and digitized in a slightly different
manner.
5. You have learned that project and layer creation can be performed ‘online’
or ‘offline’. Digitizing can only be performed ‘online’.
So, at this point you really are in command of the basics. What remains is to
discuss some of the details and special features of DLog.
Toolbar Display Operations
Pocket DLog manages the display as you digitize by maintaining a moving map.
As your travel moves the icon to the edge of the display, the active viewing scale
is reduced by a 2x step to enable visualization of all you have done to that point.
Obviously there will be times when you need to adjust the viewing scale to view
digitized features in greater or lesser detail. There are four items on the tool bar
for display operations. They are functional if you are ‘online’ or ‘offline’.
Reset. Tapping this item will change the display to whatever viewing
scale is necessary to show all digitized features in the project. Reset sets the
display to the geographic limits of the project. Tapping File | View | Reset can
also access this function.
Window. Tapping this item will put you in ‘window mode’. Windowing is a
display expansion bounded by an area that you define by 1) placing the stylus at
the start point of a diagonal, 2) dragging the stylus to the end point of the
diagonal and 3) lifting the stylus. You will notice when you tap the window icon
that the other display icons are low-lit as well as the layer selection boxes.
Window remains active with all other selections inactive until you tap the window
icon a second time to release it. Tapping File | View | Window can also access
this function.
Zoom In. Tapping this item will put you in ‘magnify mode’. Zooming in
expands the viewing scale at a point you define with the stylus. 1) tap the zoom
in icon then 2) tap the point on the display that is the center point for
magnification. You will notice when you tap the zoom in icon that the other
display icons are low-lit as well as the layer selection boxes. Zoom In remains
active with all other selections inactive until you tap the zoom in icon a second
time to release it. Tapping File | View | Zoom In can also access this function.
Zoom Out. Tapping this item will put you in ‘reduce mode’. Zooming out
reduces the viewing scale at a point you define with the stylus. 1) tap the zoom
out icon then 2) tap the point on the display that is the center point for reduction.
You will notice when you tap the zoom out icon that the other display icons are
low-lit as well as the layer selection boxes. Zoom Out remains active with all
other selections inactive until you tap the zoom out icon a second time to release
it. Tapping File | View | Zoom Out can also access this function.
Toolbar Measurement Operations
You can measure areas and distances by drawing with the stylus. Both tools are
functional ‘online’ or ‘offline’
To measure an area: 1) Tap on the area tool bar icon. Notice that all
other icons are low-lit after you tap. 2) Use the stylus to draw around the area to
be measured. When you lift the stylus the inventory feature will be closed and a
report of area and perimeter is given. 3) Tap the OK button on the report dialog
to return to general operation. Tapping File | View | Area can also access this
function.
To measure length: 1) Tap on the distance tool bar icon. As with area, all
icons are lo-lit after you tap. 2) Use the stylus to draw a line. When you lift the
stylus a report of length is given. 3) Tap the OK button on the report dialog to
return to general operation. Tapping File | View | Distance can also access this
function.
The selection arrow immediately to the right of the distance tool allows
you to select either Freehand or Survey mode for area and length
measurements. In Freehand mode, a line or area is drawn continuously with
the stylus. In Survey mode, a line or area is described ‘point-to-point’ by
tapping the stylus on points of a line or area. When the last stylus tap is
made, the line or area is assumed to be completely described. After a 2
second delay, the area or length report is given.
Position Report
You can get a position report (the coordinates of a position) by putting the stylus
on the Handheld device display.
Other Toolbar Functions
Connect to GPS. This is the same function as File | Work Offline
(uncheck).
Show GPS Status. This is the same function as File | GPS Status. It is
only active if there is a GPS connection and you are ‘online’.
Access the Data Dictionary for creation/edit.
Using Background Layers
Your work with DLog may be greatly enhanced by using background layers as an
aid to in-field navigation. DLog works with two types of background:
1) Images
2) Drawings.
The terms image and drawing are self-explanatory but there are some details to
consider:
1) Drawings and images are files that have been created outside of DLog in
a mapping or GIS system. Therefore they are (and must be to use with
DLog) georeferenced data.
2) They are transferred from your desktop to your Handheld device through
Microsoft’s ActiveSync utility. Normally, ActiveSync will have been
supplied with your Handheld device. If not, you can download the utility
from various sites on the net. Try
http://www.microsoft.com/mobile/downloads/activesync.asp.
3) Drawing and image files to be used in DLog must reside in a folder titled
My Documents. So, when you make the transfer from desktop to
Handheld device be sure that you copy the background file to this folder
on the Handheld device.
4) Drawing files may be in either AGIS *.dds_dof format or in ESRI Shape
File format. Image files may be in AGIS format, *.dds_mif or in “Geo-jpeg”
format. Geo-jpeg refers to two files, a *.jpg image and a *.jgw “world file”
that contains geographic offset and pixel dimension. Geo-jpeg is the
distribution format of Microsoft’s Terraserver site at
http://terraserver.homeadvisor.msn.com/.
5) While there is nothing to stop you from inserting a background data set
that is outside of your area of activity, the geographic extents of either an
image or drawing file should encompass your area of activity to be of any
use. It does not make sense to have a picture of the north end of your
county as a background for operations in the south end of the county.
6) Only one image file can be viewed at a time. Many drawing files may be
used at a time as an overlay on image data. The total of all image,
drawing and DLog layers in a single project is 32. Image and drawing files
can be inserted or removed from activity at any time.
7) The geography (projection, datum and extents) of an image or drawing will
effect the instantaneous transformation that happens in DLog. Under
normal operation, DLog defaults to UTM on WGS84. If you insert an
image that was georeferenced in a projection and datum other than UTM
WGS84 before you digitize in any layer, the coordinates of digitized
features will be converted to the coordinate system and datum of the
background. This is significant because there is a large amount of geospatial data on the Internet that was georeferenced in other systems
(NAD27 datum for example). If you have begun digitizing in a project and
you try to insert a drawing or image in a conflicting system you will not be
able to make the insertion. You will be given a “projection mismatch…”
error message.
Images or drawings may be inserted ‘online’ or ‘offline’. If you have a slower
Handheld device, our recommendation is to work offline when inserting images
or drawings. To insert a background image for use in a project:
Step 1. With the project of interest selected and active, tap File | Background
Layers > | Insert > | Image…
Step 2. Tap the list entry for the image to be used. Tap OK to insert the image
and return to general DLog operation.
The steps are the exactly the same for either image or drawing backgrounds.
Here is an aerial photo of Compaq headquarters. You could map your search for
iPaqs on this background.
More to the point, you could have a picture of last year’s yield (in AGIS format)
on the screen as a guide to directed sampling.
To remove a layer from project activity
Step 1. Tap File | Background Layers > | Remove > | Image…
Step 2. Tap on the list entry in the displayed list and then tap the Remove
button.
Step 3. Tap the X button to return to general DLog operation.
The background layer will be removed from display (it will not be deleted). You
can re-insert the layer in this or other projects at any time unless you have
deleted the file from Handheld device storage (system memory or external CF
card).
More About Layers
Layer | Add Defined…
Sample | Add Defined…
Very often, you do the same type of fieldwork for several clients. Rather than
creating new layers every time you create a new client, you can re-use layers
you have already defined. Note that you are only re-using the ‘structure’ of an
existing layer and not its content. Here is an example:
Grower Johnson was talking to grower Smith and he learned about the good
mapping and scouting work you had done on Smith’s farm. Johnson calls you to
do the same work for him. After you deflect all his attempts to cut a better deal
than the one Smith got, you get to work on Johnson’s place. All you have to do
to set up is:
Step 1. Tap File | New Project to create the project for your new client repeating
the same project creation steps that you took with the Smith project.
Step 2. Tap Layer | Add Defined…
Step 3. Tap the list entry titled ‘Border’ and tap OK to accept this layer already
set up with the same structure that you built for Smith. There is no content. You
will supply that uniquely for Johnson.
Step 4. Again, Tap Layer | Add Defined…
Step 5. Tap the list entry titled ‘Weeds’ and tap OK. Same structure as for Smith
but no content except that available from the data dictionary.
Step 6. Finally, Tap Sample | Add Defined…
Step 7. Tap the list entry titled ‘Samples’ and tap OK. Same structure as for
Smith. Content will be sequential as each sample is taken.
This can all be done very quickly ‘online’ or ‘offline’.
Layer | Options…
You can change the drawing color or bit map symbole for features in a layer.
Step 1. Tap Layer | Options…
Step 2. Move the horizontal slide right or left to choose a new color or bitmap.
Step 3. Tap OK when finished.
The same option is available for Sample Layers. Tap Sample | Options…
Setting an offset
You can set an offset for the digitizing of area and line features. Why would you
do this? Well, unlike Smith’s farm, Johnson’s fields are surrounded on all sides
by levees. It is easier to drive the levees than to go down in the field and drive
the edge. If you drive the centerline of the levee, the field edge is 15 feet to the
left of your line of travel. By setting an offset of 15 feet and selecting ‘Left’ you
can drive the levee and still capture the position of the field edge. Of course this
means that you have to keep the field on your left as you make the circuit. To set
an offset:
Step 1. Tap Layer | Options…
Step 2. Tap in the edit box under the title ‘Offset’ and drag your stylus over the
current value to highlight it.
Step 3. Tap the keyboard icon and type the value of the offset you want to use.
Tap the keyboard icon again to put it away.
Step 4. Use the drop down arrow to select either an offset ‘Right’ or an offset
‘Left’.
Step 5. Tap OK to save the offset.
It is very important to note that this setting becomes a characteristic of the layer
until you go back to Layer | Options… and change it.
Finally, note that you can change the length and orientation of an offset at any
time. You could digitize one feature in project: ‘Johnson’, layer: ‘Border’ with an
offset of 20 to the left and then change the offset to zero to digitize the next
feature. You could digitize on feature with an offset of 20 to the left and then
change the offset to 20 to the right to digitize another feature.
Layer | Delete
Sample | Delete
You can delete a layer from a project. This results in the physical removal of all
objects that were digitized in the layer. Deleting a layer will not remove the layer
name from a list of layer names that is maintained by DLog externally to all
projects. Layer deletion can be done ‘online’ or ‘offline’. To delete a layer:
Step 1. Use the drop down to make the layer to be deleted active.
Step 2. Tap Layer | Delete. (Or if it is a sample layer, tap Sample | Delete)
Step 3. Confirm that you actually want to delete this layer by tapping Yes on the
confirmation dialog.
Layer | Object Delete
Sample | Object Delete
You can delete an object from a layer. Sometimes you may want to re-digitize a
feature that seems to you to have been incorrectly digitized. To delete an object:
Step 1. Use the drop down to make the layer containing the feature to be
deleted active.
Step 2. Tap Layer | Object Delete (or if the object is in a sample layer, tap
Sample | Object Delete).
Step 3. Use the stylus to tap on the feature to be deleted. When you tap, the
selected feature will be highlighted and you will be asked if you really want to
delete this feature. Deletion is permanent.
Step 4. Confirm that you actually want to delete this feature by tapping Yes on
the confirmation dialog.
Layer | Object Info
You can review the attribution, including the length, area and perimeter, of any
feature you have digitized in a layer. This can be done ‘online’ or ‘offline’. This
function is not applicable to sample layers.
Step 1. Use the drop down to make the layer containing the feature(s) to be
reviewed active.
Step 2. Tap Layer | Object Info.
Step 3. Use the stylus to tap on the feature to be reviewed. When you tap, the
selected feature will be highlighted and you will be given an Object Info dialog
that reports the attributes of the selected feature. Tap the X button to return to
general DLog operation.
Some Special Features We Added at the Requests of Users
Other Layer Types
During layer creation you probably saw that there were classes of layer feature
types in addition to area, point and line.
We discussed dwell points above as a feature type to be used in creating
benchmarks by averaging a series of collections at the same location.
A Survey Area feature type was created at the request of Australians who have
very large, very rectangular paddocks (fields to you and me) to map. Rather than
drive the perimeter, collecting positions at one second intervals along the circuit,
they wanted to start at a field corner, mark a point, get into their ute (pickup to
you and me) drive a mile or so down the road to the next corner of the field mark
corner2, drive again and mark corner3, drive again and mark corner4. At corner4
they wanted to ‘close the traverse’ back to the first mark. So that is what survey
area implies, the digitizing of a field by marking its corners. A perfectly straight
line is snapped corner-to-corner. The field does not have to be four-sided. You
could use this feature type to map any shape as long as you marked each point
of deflection from a straight line along the field perimeter.
A Survey Line feature type was created at the request of drainage tile contractors
in Indiana who wanted to lay out long, straight lengths on fields in the initial
design phases of a drainage project. Rather than drive the entire run with the
inevitable drift of GPS causing variation in the collected length of a line, the
drainage guys wanted to mark an outlet point and then drive to an end point in
the field and snap a straight line between the two points. Survey Line enables
the creation of point-to-point segments. You could use survey line to build
complex segments as long as you marked each point of deflection from a straight
line along the run.
Survey Area and Survey Line layers are exclusive. This means that you cannot
mix regular area collection with survey area collection. (The same case for
regular line versus survey line collection.) The digitizing methods are different.
Digitizing a Survey Area
Step 1. Create a new layer with Survey Area designation for layer ‘Type’. Note
that attribution options are the same for any layer creation.
Step 2. Working ‘online’, position yourself at the start point of the area to be
digitized and tap the green button. Note that by tapping the green button you are
only initializing the process and not beginning digitizing. In survey area, digitizing
involves the marking of points without any intervening collection, point-to-point.
To mark the first corner point, tap the ‘red dot’ button
Step 3. Continue to each corner (or point of deflection) and tap the ‘red dot’
button at each point. Do not return to the first point of your circuit.
Step 4. When you reach the last point of your circuit, tap the red button. This will
close the traverse and pop up the attribution dialog just as would be the case in
digitizing a regular area.
Digitizing a Survey Line
Step 1. Create a new layer with Survey Line designation for layer ‘Type’.
Attribution options are the same as for any layer creation.
Step 2. Working ‘online’, position yourself at the start point of the run to be
digitized and tap the green button. As with Survey Area, tapping the green
button initializes the process. Tap the ‘red dot’ button to mark the start.
Step 3. Move to the endpoint of the run and tap the ‘red dot’ button followed by a
tap on the red button. This will snap a line from point-to-point and pop up the
attribution dialog.
Navigation to or from a Pivot Point
The pivot point feature was asked for as an assist to measuring runs by distance
and bearing to or from a set location. The initial idea was to help in the layout of
pivot irrigation systems. You establish the point, normally with reference to a
feature in a background image or drawing, and your travel is reported. This is an
‘online’ function.
Step 1. Tap File | View | Pivot Point…
Step 2. Tap the On radio button, and then tap OK.
Step 3. Using the stylus, tap a point on the screen to define the location of the
pivot point. A block symbol for the point will appear with a line snapped between
the point and your current location. Your distance and bearing to the pivot point
will be continuously updated as you travel toward or away from the point.
To turn the pivot point function off, tap File | View | Pivot Point…. Then tap the
Off radio button on the pivot point dialog and tap OK. If you turn the pivot point
function back on, the original pivot point will be displayed. Change pivot point
location by tapping a new location.
ALTERNATELY…
You can set your current GPS position as the pivot point by tapping in the “Use
Current GPS Position” check box. The distance and heading of your travel from
your GPS-marked position will be annotated.
Calculating the Radius of a Pivot Circle within a Field
This was another request from the irrigation people for a useful feature. The
scenario is this: You have mapped a field boundary. Now you want to see what
the size of a pivot circle would be that fits inside the field.
Step 1. Digitize the field boundary. Note when the boundary has been digitized
that a point has been placed at the geometric/geographic center of the field. This
would typically be the pivot point for the field. However, if the boundary is not an
approximate square, that is it has a very irregular shape, you may find that the
center is offset from where you might have imagined it to be.
Step 2. Tap Layer | Radius
Step 3. Put the stylus at the center point of the field and drag the stylus away
from this point. A ‘rubber band ‘ circle will follow the drag. When the limit of the
circle reaches a point you accept as workable within the field, lift the stylus. This
will pop up a report of the circle radius length and circle area.
Tap on Continue… to draw another radius.
Tap on Save to add this radius circle as an object in a layer titled “Radius”. This
first operation of Radius | Save will create the layer in the current project.
Thereafter, any operation of Radius | Save will append to that layer. The layer
is a *.dds_log file and its content may be exported to a GIS or mapping
application. So, if you are someone who does irrigation work, you can do a lot of
estimation quickly and get the results to your customers.
Tap OK to return to general DLog operation.
Getting your field work to other systems
We call DLog a digital mapping system. The point of digital mapping systems
has always been to supply content to graphic and geographic information
systems. In this regard, DLog is no different. Your DLog work can be exported
to many GIS, mapping and CAD systems through one of several export formats.
These are:
1)
2)
3)
4)
*.shp
*.mif
*.dxf
an x,y,z *.txt file.
Pocket DLog Converter is a free utility. Its function is file conversion. It is
operated from your desktop computer and communicates with the Handheld
device through Microsoft’s ActiveSync. An ActiveSync connection must be
established before Pocket DLog Converter can be used. This means:
1. ActiveSync has been installed on your desktop computer.
2. Connection settings are made as follows by clicking File | Connection
Settings… on the ActiveSync interface.
3. The Handheld device has been placed on its cradle and the cradle has
been connected to the serial port of your desktop. A connection will be
established as soon as the Handheld device makes contact with the
cradle.
Moving and converting DLog files with Pocket DLog Converter.
Step 1. This is a desktop program. Start the program on your desktop. This
dialog pops up:
A list is given of all DLog files in all projects currently resident on your Handheld
device. If you do not see the list entries, click on the Refresh button.
Step 2. Select the files to be moved and reformatted by clicking on the list entry
for each selection.
Step 3. Select the output format by clicking on the drop down arrow under
‘Export Type’ and clicking a selection. In this case we are selecting ‘ESRI
Shape’ as the export format.
Step 4. Click on the Browse button next to the ‘Export Folder’ text box. Use the
Windows File Open dialog to set the target folder for this operation.
Step 5. Click on the Reformat button to initiate processing.
Mapping and analysis would proceed in ArcView or an ArcView-based product
through the creation of themes using the *.shp files produced by DLog. The
same process is applied to data in any of the other export formats.
Working with DLog files in Delta Data Systems’ products.
Delta Data Systems created DLog. A DLog import feature is in each of its
Precision Ag products, AGIS, ViewPoint and TilePro. Making DLog data
available to these products involves a copy of DLog files from the Handheld
device to your desktop and subsequently, accessing the DLog import function
during AGIS, ViewPoint or TilePro operation.
To copy DLog files from Handheld device to desktop (There are several
methods, this is one recommendation.)
1. Establish a connection between Handheld device and Desktop through
ActiveSync.
2. On your desktop, open the first of two Explore windows (Start | Programs
| Explorer) and point to the target folder on your desktop.
3. Open a second Explore window and point to the source folder on your
Handheld device (called Mobile Device by Explorer). The source folder is
always titled LOGPROJECTS. This folder can be on the system memory
of your Handheld device or it can be on removable media such as a CF
memory card.
4. The DLog files to copy are located in folders under LOGPROJECTS that
bear the name of the projects you created. They have the suffix,
*.dds_log. No other files should be copied. Select and copy DLog files
from the source folder to the target folder. They are available for import in
AGIS, ViewPoint or TilePro at that point through Tools | Import Image… |
DLog.