Reflective Survey Targets used on the One World Trade Center's Transportation Hub
Rothbucher Systems RS90 Retro Reflective Angle Survey Target w/ 3 Target Reflectors (40x40mm)
Ranges:
Target reflectors w/ cross hair 30 x 30 mm: range approx. 80 m (262 ft)
Target reflectors w/ cross hair 40 x 40 mm: range approx. 100 m (328 ft)
Target reflectors w/ cross hair 60 x 60 mm: range approx. 120 m (393 ft)
The ranges are average values and will be greatly exceeded by the majority of current total stations, some of them need a minimum distance of 10 meters.
Attention:
It is recommended that only reflective targets are used for distance measurements with tachymeters or total stations.
Targets with cross-hairs (non reflective) are offered specially for use with auto levels, theodolites and construction lasers.