Photo 1: GPS receiver GP-E2
GPS Receiver GP-E2
Append location information and shooting directions to images
GPS logging function records travel routes
Automatically set GPS time on the camera
Display shooting locations and travel routes on computer maps
This month's technical report delivers technical information on the GPS receiver GP-E2.
Overview of GPS receivers
The Global Positioning System (GPS) is the core system that enables navigation functions on cars and mobile phones. The system consists of about 30 GPS satellites that orbit the earth to cover all parts of the global.
The GPS receiver GP-E2 (Photo 1) is a camera accessory for the digital age that picks up signals from GPS satellites. This allows the GP-E2 to append information like the shooting location and time to images and to record routes traveled in its internal memory.
Users can display photos and where they were shot on computer maps, making it possible to enjoy the memories of vacations or hiking trips through both photos and maps. The GP-E2 lets users identify shooting spots even when photos are taken in places where it is difficult to ascertain the shooting location, such as at sea or off-road in the mountains.
Feature 1 - Append location information to images
• Compatibility between the GP-E2 and cameras
The GP-E2 can communicate with any camera [*1] that displays the GPS device settings menu option (Figure 1) just by attaching the receiver to the hot shoe (except for the EOS 7D). With communications established, the GP-E2 can tag images with the latitude, longitude, elevation, and UTC [*2] when the shot was taken (Figure 2). Cameras can also make use of the GP-E2's digital compass and auto time setting. EOS 5D Mark III and EOS 7D cameras may require a firmware upgrade if the GPS device settings menu option does not appear.
With cameras that do not have the GPS device settings menu option, the GP-E2 can still be used to record the travel route in its internal memory. Images can be tagged with location information later with the bundled Map Utility application.
*1. The digital compass and auto time setting functions cannot be used with the EOS 7D. Additionally, the GP-E2 cannot communicate with the camera just by attaching it to the hot shoe: a cable connection is necessary.
*2. UTC stands for Coordinated Universal Time. It is virtually the same as Greenwich Mean Time.
• GPS function
After turning on the GP-E2's power switch, it starts scanning for GPS satellite signals. The signal is usually acquired in about 30 to 60 seconds under favorable conditions. After signal acquisition, the GP-E2 moves to standby mode, but it will send location information to the camera when the camera starts up or shoots an image.
The GP-E2 is more sensitive than the GPS function on the EOS 6D and can receive satellite signals more readily in poor reception areas.
Note that to append the elevation to images, the GP-E2 must receive signals from at least four GPS satellites. Users can check the satellite reception status on the GPS information display (Figure 2). In general, when the Satellite reception reads 2D, the GP-E2 can tag the latitude and longitude to shots, and when it reads 3D, the receiver can also tag the elevation.
Feature 2 - Digital compass
The GP-E2 has a built-in digital compass that can record the direction a photo was taken in. The digital compass is not related to GPS; the direction is measured by detecting geomagnetism. Note that the GP-E2's digital compass bases its direction measurements on magnetic north and not the true north of the earth's axis. Users can check the direction the camera is pointed in when shooting on the LCD monitor (Figure 3).
We recommend that users calibrate the digital compass (Figure 4) after attaching the GP-E2 to the hot shoe in the shooting location to ensure the accuracy of camera direction measurements.
Feature 3 - Recording travel routes
• Logging function
The logging function records the current location information in the GP-E2's internal memory at a fixed interval that can be set between one second and five minutes (Figure 5). To set the most appropriate interval, consider the speed you will be traveling at. Turning the power switch to LOG will have the unit scan for GPS satellite signals and start logging location information.
Logged travel routes can be displayed on computer maps. Note that if you are logging location information while the GP-E2 is inside a bag or other container, be sure to set the GP-E2 so that it faces up and leave it uncovered so that it can receive GPS signals easily. Users can put the GP-E2 in its carrying case and wear it on their belt, for example (Figure 6).
A new log file is generated each day, but the start time is based on Coordinated Universal Time. Consequently, in Japan for example, location information is recorded in a new file for 24 hours beginning from 9 a.m. each day.
• Cameras and log file compatibility
Even with cameras without the GPS device settings menu option, it is still possible to append log file location information to images using a computer as long as the images were taken with a Canon camera.
After loading the log file and the images into the computer and running the bundled Map Utility application, each image will be tagged with the closest previous recorded location information based on the image's shooting time.
• Update interval, number of log files [days], and estimated battery life
Table 1 indicates the location information update interval versus the number of log files [in days] that can be recorded and the estimated battery life [in hours]. When the internal memory is full, new log files will overwrite other files starting with the oldest log file.
Note that due to the nature of GPS, the update interval will vary somewhat.
|Position update timing||Log files capacity [in days] [*1]||Estimated battery life [*2]|
|1 sec.||4.5||10 hours|
|5 sec.||23||27 hours|
|10 sec.||45||37 hours|
|15 sec.||68||39 hours|
|30 sec.||128||39 hours|
|1 min.||128||54 hours|
|2 min.||128||63 hours|
|5 min.||128||92 hours|
*1. Capacity when logging eight hours per day
*2. Battery life when using an AA/LR6 alkaline battery and operating at room temperatures.
Battery life will be shorter if used in areas with poor GPS signal reception.
Feature 4 - Display travel routes and shooting locations on maps
Users can view the shooting locations, the photos, and the route they traveled on a computer map using the bundled Map Utility application, which works in conjunction with Google Maps™ (Figure 7). The shooting direction is also displayed for images tagged with digital compass information. If the shooting location can be displayed on Google Maps, images shot anywhere in the world can be displayed on a map. Note that Map Utility requires an Internet connection to access Google Maps.
Map Utility also lets users load and delete log files, configure the GP-E2, and output Google Earth™ files in addition to mapping with Google Maps.
Feature 5 - Auto time setting
The GP-E2 can be used on cameras that have the GPS device settings menu option to set the camera's internal clock to the time information received from GPS satellites. The GP-E2 must receive signals from at least five GPS satellites to set the time. Selecting Auto update and turning on the GP-E2 will automatically update the time when satellite signals can be acquired.
The accuracy of the time setting is about ±0.02 seconds on the EOS-1D X and EOS-1D C and about ±1 second on other cameras.
Feature 6 - Accessories
The GP-E2 comes with the accessories shown in Figure 8. For example, with the carrying case and the approx. 1.5-meter cable, users can use the GP-E2 and an external flash at the same time, by clipping the GP-E2 in its case to their belt and connecting the receiver to the camera with the cable. The approx. 25-centimeter cable is for connecting the GP-E2 to the EOS 7D and to other cameras when mounted on the optional AB-E1 accessory bracket (Figure 9).
Countries and regions where the GP-E2 can be used
The GP-E2 can be used in the following countries and regions (as of May 2013).
Hong Kong, India, Japan, Macao, Mongolia, the Philippines, Singapore, Vietnam, Canada, United States, Argentina, Brazil, Cayman Islands, Colombia, Ecuador, El Salvador, Guatemala, Honduras, Aruba, Panama, Paraguay, Peru, Venezuela, Austria, Belgium, Bulgaria, Cyprus, Czech, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Kazakhstan, Latvia, Liechtenstein, Lithuania, Luxemburg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Russia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Ukraine, United Kingdom, Australia, French Polynesia, New Caledonia (France), New Zealand, Israel, Oman, Turkey, Curacao (the Netherlands), British Virgin Islands, United States Virgin Islands, Bosnia, Croatia, Georgia, Macedonia, Lebanon, Saudi Arabia, Kaliningrad
GP-E1 and EOS 6D's GPS function
Table 2 compares the GP-E2 with the GP-E1 for the EOS-1D X and EOS-1D C and the GPS function on the EOS 6D.
|GPS functions||Latitude, longitude, elevation, UTC, satellite reception status|
|Auto time setting||Yes|
|Power supply||One AA/LR6 battery||Uses camera's power supply|
|Dimensions (w x h x d, approx. mm, measured according to CIPA guidelines)||54.3 x 72.9 x 44.2||24.7 x 57.0 x 35.7||144.5 x 110.5 x 71.2*|
|Weight (approx. grams), unit only||84||44||680*|
* Size and weight of the camera body.