The prism constant for Leica prisms, when used with Leica instruments, are as follows:
| Leica Prism Type | Leica Prism Model | Absolute Constant | Leica Constant |
|---|---|---|---|
| Leica 360° prism | GRZ122, GRZ4 | -11.3mm | 23.1mm |
| Leica mini 0 | -34.4mm | 0.0mm | |
| Leica mini 360° prism | GRZ101 | -16.9mm | 17.5mm |
| Leica mini prism | GMP111, GMP101 | -16.9mm | 17.5mm |
| Leica reflective tape | 0.0mm | 34.4mm | |
| Leica round prism | GPR121, GPR111, GPR113 | -34.4mm | 0.0mm |
| Any surface/reflectorless | 0.0mm | 34.4mm |
Download an image of the above Leica prism constant chart here.
Leica Prism Constants When Used With Trimble
To calculate the prism constant to use for Leica prisms with Trimble survey instruments you subtract 34.4mm from the Leica prism constant value.
Leica prism constant – 34.4mm = Trimble prism constant
Using the Leica 360° prism as an example:
+23.1mm – 34.4mm = -11.3mm
When using a Leica prism with Trimble surveying equipment, the prism constant for the Leica prisms are:
| Leica Prism Type | Prism Constant (In Trimble Instruments) |
|---|---|
| Leica 360° prism | -11.3mm |
| Leica mini 0 | -34.4mm |
| Leica mini 360° prism | -16.9mm |
| Leica Mini Prism | -16.9mm |
| Leica reflective tape | 0.0mm |
| Leica round prism | -34.4mm |
| Any surface/reflectorless | 0.0mm |
Download an image of the Leica prism constant chart when using Trimble surveying instruments here.
FAQs
What Is the Absolute Prism Constant of A Leica Prism?
The absolute prism constant of a Leica prism is -34.4mm.