MAGNET Field: Creating a custom prism

Is your prism not on the list? No problem. This quick guide explains how to add a custom prism in MAGNET Field.

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MAGNET Field: Creating a custom prism

Navigating to the configuration

Click Configure.

Click Survey.

Click Edit to edit your total station configuration.

Click Next until you reach the Survey Settings screen. 

This screen allows you to customize the prism for the foresight and backsight. This is useful if working with different prisms on the same jobsite.

The Prisms screen has a predefined list of specific prism models. 

If your prism is not on this list, click New to create a new custom prism.

Custom prism

Name: Name the prism according to brand or type.

Constant: Enter the prism constant. This is the parameter of the prism defining the difference between the reflection plane and the center of the prism. This is usually specified on the prism or in the manual.

Hybrid Positioning: If you are using hybrid positioning (GNSS and optical), the antenna offset is the difference between the center of the prism and the receiver's antenna reference point (ARP). 

Height Type: Click on the drop-down list to select height type. Use Center of Prism if you are directly measuring the height from the pole tip to the center of the prism during your survey. If using Center of Prism as the height, the center offset is disabled.

Only use Top of Pole if your pole is consistently the same height during the ENTIRE job. For this setting, you just need to enter the pole's height in the Center Offset field. MAGNET Field will automatically add the prism offset to the height of the pole. 

For example, let's say you create a custom prism that uses Top of Pole and have the pole height entered as 6 ft. When shooting a point with that custom prism, MAGNET Field will automatically set the pole height as 6 ft because of the custom prism. To avoid accidentally doubling a height when using this custom prism, enter the height as zero.

Once done creating your custom prism, click on the green check mark to save your configuration.

Click on the yellow dot next to your prism name to use the custom prism. You should see the green check mark appear next to your custom prism. 

Click the green check mark in the upper right hand corner to save.