> 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:

Then add both to a session:

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!

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