Knowing the full distance to the pin, the carry over water, the width of the fairway to the nearest yard can provide serious practical help when it comes to making a club selection. With this information to hand, there’s a real chance of lowering your score in medal play or taking strokes off your handicap.
Tour pro caddies have always kept extensive yardage information in their note books gleaned during practice rounds and they too can use the latest technology. So if its good for them it should be certainly considered as the next weapon in your golf equipment armory!
Typically a rangefinder will use an invisible Class 1 laser beam that is safe to the eye which is bounced off a target at the press of a button. The unit’s internal digital clock then measure the time taken for the outward and return journey and immediately calculates the distance, which it then displays.
Targets can take many forms including the flag on top of the pin, to trees and other hazards. Now the major advantage of a rangefinder is that you can go to any course, any time, take the unit out of your bag and get measuring. Their disadvantage is the target has to be within line of sight. So it can’t be used from the tee to a hidden green for example.
In a similar vein to those used in cars, Golf GPS units work off Global Positioning System satellites which transmit information to ground equipment. These receivers passively collect information – they do not transmit any. Each satellite continuously transmits data about its current time and position. The lapse in the time taken for this information to be received from each satellite varies enabling the receiver to estimate, based on a minimum of four satellites, its position in three dimensions. For more technical information on these systems go to
To harness this wealth of data for golfers means that someone needs to identify grid references, at the very minimum, for the golf green. The unit then knows where you are and the distance to it. More sophisticated units can take in much more information such as the position of bunkers, water hazards and trees to mention but a few. Some even more sophisticated Golf GPS trace the green’s perimeter enabling distances to be calculated from any approach angle.
One of the main advantages in this type of system is that you don’t have to aim at the target to get a reading. Ideal where there is no line of site as a result of a hidden green, a dogleg or a stray drive in the woods! This aiming can be a rangefinders Achilles heel resulting from wobbles and the problems of very small targets, although better units have stabilising systems. But all GPSs have disadvantages too – someone has to survey the course first and you have to down load and possibly pay for it, although there are some units that you can program yourslef but that in itself can waste valuable time. However this may not be such a problem if you only play a few courses.