GPS Data Collection for Area Feature
“I currently have iCMTgisII on my ipad. I am looking for the simplest and quickest way to measure acreages using track points. what is the quickest way to achieve this using that program?”
You can use the GPS/Collect function to record an Area Feature while walking or driving along the perimeter of an area you wish to measure. The standard procedure is to first define a Feature List suitable for your project to facilitate data collection. However, if you just want to quickly map an area, you can use the following steps.
1. Tap on the GPS icon then select “Turn GPS ON“. Wait 5 – 10 minutes for it to stabilize..
2. Select GPS – Collect.
3. Tap on the “Area” tab.
4. Enter the Feature Topic Name, such as “area”. The app automatically assigns “area001” as the first Feature ID.
5. Tap on the Store button in the data collection panel then start walking. By default, one GPS fix will be recorded per second.
6. When you have walked around the area and come back to the starting point, tap the Stop button.
7. If you want to record another area, go to the start point for that area and tap on Store. The app will have assigned area002 as the Feature ID for this second area.
8. When done with the data collection, tap on the Exit button.
9. Back in the Map View, tap the Zoom-Fit icon to see all the areas in the screen. Tap on one of the areas to highlight it. Tap on the Feature Properties icon then tap on the “Length/Area” tab to see the perimeter and area values.
One thing to note is that the GPS on your iPAD is not quite accurate. It is probably fine for measuring very large acreages. For better accuracy (2-5 meters), many of our app users use a compatible external GPS receiver, such as the Dual XGPS-150A or the Bad Elf GPS. GPS receivers that provide sub-meter accuracy, such as the iSXBlue II and the EOS Arrow, have a higher price tag.