Equipment for Data Collection
This page documents what equipment is recommended for data collection using PaleoCore workflows and data collection protocols. These recommendations are based on three years of field testing in Ethiopia in relatively rugged conditions and without internet or cellular connections. A full equipment package, including the apps, should cost approximately $500-$1000 depending on the device purchased.
Models prior to the 4S lack an internal GPS, which is necessary for accurate positioning in remote areas without a cellular network. Model 4S phones can be purchased online and are cost-effective for field use. In order to install software the phone will require a SIM card even if the phone is never activated on a cellular network. SIM cards can be purchase online or you may be able to get them free of charge at ATT stores or from other mobile providers.
The iPad mini offers the best balance between size, weight and battery life. Another benefit of the iPad mini when used with the GIS Pro app is that the screen is large enough that the data entry widgets on the sidebar do not completely cover the map.
The wifi only versions of the iPad do not include a built in GPS, however they can be connected to an external bluetooth GPS. The wifi+cellular models come equipped with an internal GPS and this is recommended for field work because it provides the option of using the device without depending on an external GPS. Cellular service is not required to use the built in GPS on a wifi+cellular iPad mini.
The iPad mini comes in a 16 GB, 64 GB and 128 GB models. We've used 16 GB models in the field for two seasons without storage space issues. The GIS data files are small. Images can take up substantial space. The iPad mini hosts a 5 megapixel camera and the resulting images are roughly 1.5 MB in jpeg format. A 16 GB mini dedicated for field work has sufficient space for all necessary apps, data and imagery. Larger storage may be needed if additional apps are required or if you plan to take and store a lot of video.
The iPad and iPad Air are best for visualizing or digitizing data but can be cumbersome to carry around for full-day data collection. They're excellent for geological field mapping or for mounting in vehicles for navigation. The wifi only versions of the iPad do not include a built in GPS, however they can be connected to an external bluetooth GPS. The wifi+cellular models come equipped with an internal GPS and this is recommended for field work because it provides the option of using the device without depending on an external GPS. Cellular service is not required to use the built in GPS on a wifi+cellular iPad mini.
An external Bluetooth GPS is mandatory if using a wifi only iOS device. It also helps extend battery life in the field. We've had success with the Bad Elf 2200 GPS Pro and the Dual Electronics XGPS150A. The Bad Elf has the advantage of an independent display on the device so that it can be used on its own without connecting to an iOS device. The XGPS does not have a screen and must be connected, however it comes with a very handy no-slip dash mount that makes it very convenient for use in vehicles.
It is worth bearing in mind that iOS devices restrict acess to the raw GPS data stream. Instead iOS Location Services manages information from the internal GPS, external GPS and cellular network to determine a location and then sends the location information to the apps. Depending on your perspective this may be a benefit or limitation of iOS.
We recommend purchasing some form of external protection for the device such as an otterbox.
We recommend a spare power supply for the devices such as the Anker lipstick charger. Each device should also have backup lightning cables.
The current recommendation for data collection software is GIS Pro by Garafa Software. This is an expensive app. Each license costs $300 but it is a fully featured GIS that allows one to configure data collection forms directly on the device and copy them between devices. GIS Pro inlcudes a function to cache base maps from online sources such as Google and Bing, but this feature can be unreliable. We have also experienced frequent crashing of GIS Pro during field work but the app does recover quickly and no data are lost when the app crashes.
GIS Pro can export data in several formats including KML/KMZ, shapefile and CSV. Unfortunately none of these options is ideal. KML/KMZ does not have a standard for the structure of the attribute data. Shapefiles do have structured data but have a very low limit for the length of field names in the data table which can lead to awkward truncation of field names. The CSV option only works for point features. An ideal format would be geo-json but as yet this is not available.
- Device (iPhone, iPad) with SIM card if necessary
- External Bluetooth GPS (if desired) with charging cables (for external GPS)
- Ruggedized Cover
- Backup Power supply and charging cable (for power supply)
- Backup lightening cables for the device
- GIS Pro app