Knowledge Base

Problem

The camera lens does not cover the entire observation area, causing the subject (e.g., fish, rodent) to swim or move off-camera. The user cannot see the full arena in Arena Settings and is unsure how to view the live camera feed to verify coverage.

Details

Symptoms include the animal moving outside the visible frame during trials, the arena boundary extending beyond the camera's field of view, and the live camera image in Arena Settings not showing the complete observation area. Can occur after transport (which may shift lens settings) or when using a lens that is mismatched to the camera resolution, frame rate, or distance. Reported in EthoVision XT with zebrafish well plate and Petri dish setups; likely applicable to any arena type.

Solution

1. Open EthoVision and navigate to Arena Settings. Use the live camera image to verify that the complete observation area (well plate, Petri dish, maze, etc.) is visible within the frame.
2. If the area is not fully visible, check the physical lens setup. Confirm the lens is appropriate for your camera resolution, frame rate, and working distance (height of camera above arena).
3. If the lens was recently transported, check whether the zoom or focus ring has shifted and readjust as needed.
4. If using a Basler GigE camera, open Pylon Viewer and adjust the Area of Interest (AOI) or resolution to ensure the full arena is captured. See also: 'Camera Field of View Incomplete – Adjusting Camera Resolution and AOI in Pylon Viewer for EthoVision'.
5. Raise or lower the camera mounting height (e.g., on an autopole) to widen or narrow the field of view as needed.
6. Once the full arena is visible in the live feed, proceed to define the arena boundary in Arena Settings to match the visible observation area.