What to do when GPS signals are blocked by heavy canopy?

“I am currently using the program to plot a property line for our vineyard. One of the corners of the property is tucked deep within some woods where satellite reception is poor. Therefore, the program is not allowing me to record the point. Is there any way to work around this? Perhaps increase the rms limit to within several feet so as to allow for data collection? Thanks for the help.”

This is why iCMTGIS PRO provides the Traverse function to deal with a situation where GPS signals are blocked by heavy canopy. How far is this corner away from a point at which you have good satellite signal reception? What you could do is to record a good point at the periphery of the wooded area then measure the distance and bearing from this point to that corner. Then you will use the Traverse function under GPS – Collect data to specify the GPS point as the starting point and enter the distance and azimuth or bearing information to create the corner point.

You could try and see if you could record the point by relaxing the RMS limit and the DOPS limit, but the position accuracy will be compromised.

If the accuracy requirement of this point is not strict, and you are able to identify the location of this corner on a background map, you could digitize it by using the Add Point Manually function. Zoom in to better place the point.

If you have a deed document including the property description (distances and directions around the perimeter), you could use the Deed Calls function to enter such information in iCMTGIS PRO to draw all or part of the property boundary as a reference for digitizing the corner point.

After you have created the corner point, you can add it to the remainder of the GPS’d property boundary Area by using the Insert Node function.

Custom Symbol Assignment in iCMTGIS PRO

“I have two clients using iCMTGIS Pro and they’re asking how to save custom feature symbols, colors and patterns in a feature list. For instance, how do you manage various patterns/colors for several area features, lines and points?”

In the Help document please select “Set up Feature List”.

Under “Editing a Feature List”, there is this instruction:
“Mark the Activate Pattern checkbox to see the Pattern column displayed in the Value section.” After marking the Activate Pattern checkbox,  you will be able to assign different symbols, colors and patterns to different types of Points, Lines and Areas on the active Topic layer.

After you have saved the Features List, you will be able to select that Feature List to use with a Job. You can do so in the Job Setup screen after selecting Job – Open Job.

If the clients are looking to create their own custom symbols, then they would need to use PC-GIS X to edit the symbols on one of the symbols pages (such as Forestry1, Forestry2 or Surveyor) then use iTunes to copy the corresponding symbols library file to the documents folder for iCMTGIS PRO. For example, for the point symbols, the file names corresponding to Forestry1, Forestry2 and Surveyor are cmtpnt01.lib, ctpnt02.lib and cmtpnt03.lib, respectively. Please note that these files are case sensitive in iCMTGIS PRO. Close the app by double-clicking the Home button of the iOS device. Then reopen the app to see the available new symbols.

User-defined projections

“. . . we would like to know by PC-GIS software possible to establish our Coordinate system (KTM Projection and GRS 1980 Datum) to use it in iCMTGIS Pro software?”

The KTM-KUDAMS projection for Kuwait is based on the Transverse Mercator projection. You can use the PC-GIS X software to create a user-defined coordinate system by entering the parameters for this projection. Then please copy the user_cor.sys file created by PC-GIS X to your iCMTGIS PRO documents folder. Then iCMTGIS PRO will let you select the user-defined coordinate system to use.

Direction of deed calls line segment

“I just bought Deed Calls Pro and I was wondering when adding a line segment with bearing information how to get the line to go the other direction. For example: N54°3740W draws the line in the wrong direction.”

Please note that, in the deed plot you are doing, the green node is the last starting node. The line segment does go from the green node to the yellow node in the NW direction. If you enter a long distance, you should e able to see the line labeled with the correct bearing. If you wish to change the direction, then change the bearing of the line segment.

Using iSXBlue II with iCMTGIS PRO

A customer using iSXBlue II GNSS with iCMTGIS PRO on an iPad mini 2 sent us a few question:

1) He wondered how to tell if the iPAD running iCMTGIS PRO is operating with the external SX Blue II.

With the iPad paired over Bluetooth with the iSXBlue II GNSS, tap on the GPS icon and select “Turn GPS on”. A GPS marker should appear and the app should issue a navigation beep once every second. This indicates that the app is receiving the GPS position data from the iPad, to which the iSXBlue II is sending the GPS signals.

Now, tap the GPS icon and select “Turn GPS off”. Select Main Menu – Setup then select GPS. In the GPS Setup screen, select “Enable the external GPS” then select “GNSS RECEIVER”. Set the threshold values as desired then tap on OK.

When you tap the GPS icon and select “Turn external GPS on”, a GPS status line should appear at the top of the screen, showing the number of satellites used, the PDOP value, etc. This indicates that the app is obtaining the GPS data directly from the external GPS/GNSS and not just getting the GPS position from the Apple CoreLocation.

2) With respect to the iSXBlue RTN NTRIP app, he asked, “I have this app and presume both your app and this one need to be open and running at the same time?”

RTK work means you are making use of the correction data sent out by a RTK network provider. Therefore, both the iSXBlue RTN NTRIP app and iCMTGIS PRO need to be open and running at the same time.

How can I make sure I’m capturing points meeting a PDOP threshold?

If you are using iCMTGIS PRO and an iSXBlue II or EOS Arrow GPS receiver, you can set the PDOP limit for GPS data collection as follows:

1. Turn off GPS from all apps on your iOS device.

2. Select Main Menu – Setup and mark the check box for “Enable the external GPS“.

3. Select the appropriate device protocol for the GPS receiver.

4. Tap on the pull-down arrow for PDOP Mask and select the desired PDOP Mask level. If you only want to record position data for which the elevation can be computed, then also mark the “3D Only” check box. Tap on OK to save the setting and close the screen.

5. Tap on the GPS icon then select “Turn external GPS on”.

iCMTGIS II closes after iOS 10 update on iPad mini

“I have a copy of iCMTGIS II, recently updated/last week, running iOS version 10.2.1 (14D27) on iPad mini/gen 2. With ‘gps on’ and upon tapping ‘Collect’ to collect data, the app closes and doesn’t allow data to be collected. The app remains open in the background, i.e. doesn’t close out, but upon selecting ‘Collect’ again, it repeats the same issue and will not allow data collection.”

We asked the user, “Have you tried uninstalling and reinstalling the iCMTGIS II app?”

The user replied, “the un-install/re-install worked. . . . thought of un-installing/re-installing but had never done that with an iOS app since it is a download from the app store, but now I know I can. thanks!”

It is possible that the iCMTGIS II app was still open when the user did the iOS upgrade. Before an iOS upgrade, it’s best to close out all running apps. You can do so by double-clicking the Home button then swiping up the displayed app screens.