> For the complete documentation index, see [llms.txt](https://support.senterasensors.com/home/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.senterasensors.com/home/fieldagent-mobile-ios/60-second-guides/ground-control-points.md).

# Ground Control Points

Learn how to capture GCPs for a field.

***

## Motivation

I want to record Ground Control Points (GCPs) for my field.

***

## Requirements

You must have [Trimble Mobile Manager](/home/fieldagent-mobile-ios/60-second-guides/trimble-mobile-manager.md) and your DA2 configured.

{% hint style="success" %}
The resulting feature set will be attached to the field you have selected.

The app will calculate an offset of `-2.0m` for all points to offset your survey rod.
{% endhint %}

***

## Steps

From the Home Screen:

1. Tap on your field.
2. Tap on the Points button.
3. Tap on the + button on the top left.
4. Tap on Ground Control Points.
5. Move your DA2 over the point you wish to record.
6. Wait for the app to report `0.01 m` accuracy and for the Current Location to display a <mark style="color:green;">**green**</mark> status.
7. Tap Save Location.
8. Repeat until all the points have been surveyed.
9. Tap the Save button on the top right.

{% hint style="success" %}
The app has saved the data locally to your Apple Device.&#x20;

You can either upload later or start the upload now.
{% endhint %}

From the Field Point Details screen:

1. Tap the Upload button.
2. Verify your network connectivity by reviewing the network indicators.
3. Tap the Upload button to start processing.

Once the upload has been completed, tap the Done button to return to your Field Point List.

<figure><img src="https://3961074089-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FZgxcabwSCSKC3cebaIwD%2Fuploads%2FRzmyLXgccNhZkxASawGW%2FGCPs.gif?alt=media&amp;token=00f8dab2-3007-4289-94cb-4df60c9d4a2b" alt=""><figcaption><p>Ground Control Point Capture</p></figcaption></figure>


---

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