GPS satellites have been freely accessible to the world through the "public good" policy of the United States Air Force and their NAVSTAR Global Position System (GPS.) It is a system of satellites that broadcast a specific radio signal to connect to a receiver like this one. If three or more of the NAVSTAR satellites are in transmission range of the GPS unit, through simple mathematical calculations based on the distances between each orbiting satellite and the receiver, a 3-dimensional position on the X/Y/Z axes is determined. This in turn translates into latitude, longitude and altitude co-ordinates on a GPS receiver.
Geotagging has become an important part of digital photographic organization, classification and notation. The process involves obtaining coordinates through GPS triangulation, and embedding them in a way that allows a photographer to store the location to which the photograph was taken within the digital image file itself. In order to generate these coordinates, a GPS receiver like the Holux M-241 is required.
The Holux M-241 is an extremely versatile GPS datalogger and receiver. It can pair via a Bluetooth or USB connection to a compatible device like a PDA, computer, or a digital camera with the use of a Red Hen Systems Blue2CAN Bluetooth adapter. When used this way, active signals are passed giving real-time coordinated to the paired device. Another way the Holux M-241 may be used is as a datalogger where it stores an electronic path (a tracklog) of a journey and will save it in a choice of four formats: KML, NMEA (text) GPX, or binary. This file can be transferred to a computer whereby using a geotagging application, the time stamp on the image can be matched to a time and location stored in the tracklog.
When using the Holux M-241, the status of the device can easily be determined with a glance at its LCD screen. Location information, speed, memory size, date and time are all presented for a user's convenience.
