> For the complete documentation index, see [llms.txt](https://docs.ceruleansonar.com/c/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ceruleansonar.com/c/sonarview/session-configurations/omniscan-+-altitude-source.md).

# Omniscan + Altitude Source

The Omniscan can support multiple devices as altitude sources. The sonar can adjust its imagery so that the water column — the empty space between the sonar and the seabed before the seafloor return arrives — is removed from the display.

You can use either the S500 Sounder, Surveyor 240-16, or the Blue Robotics Ping as an altitude source. Start by adding both the Omniscan and Sounder as devices:

<figure><img src="/files/A01dF1zx1lwV9goinKoD" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/NCjKAMlkcSjbgxjvBDpP" alt=""><figcaption></figcaption></figure>

Then add both to a session:<br>

<figure><img src="/files/LfGrXsl3kUI6QId0vNik" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/YLf2XEpyYzC5wbsyGAze" alt=""><figcaption></figcaption></figure>

You can then exit Session Configurations, start Discovery, and connect to the session. Once connected, start pinging. In the right display control's panel, you will see a Depth Compensation header. Under source, choose the S500 and you're good to go!<br>

<figure><img src="/files/7qm2P9sEHU3j5UWhFmM1" alt=""><figcaption></figcaption></figure>

{% hint style="info" %}
This example just used the S500, but the same steps will work for the Surveyor and the BR Ping
{% endhint %}