Knowledge Base

Problem

User has set up new Basler GigE cameras for EthoVision and needs to adjust the zoom to ensure the full arena is visible in the camera's field of view. They are unsure how to physically adjust the camera lens.

Details

Noldus-supplied GigE cameras for EthoVision typically ship with a varifocal (zoom-adjustable) lens. The lens has two manually adjustable rings: a zoom ring (controlling focal length / field of view width) and a focus ring (controlling image sharpness). Users unfamiliar with the hardware may not know these rings exist or how to use them. Applies to standard Basler GigE camera packages supplied with EthoVision XT systems.

Solution

1. Identify the lens on your Basler GigE camera. Standard Noldus-supplied lenses are varifocal with two adjustment rings.
2. The zoom ring (often marked Wide–Tele or W–T) controls how wide or narrow the field of view is. Rotate toward Wide (W) to see more of the arena; rotate toward Tele (T) to zoom in.
3. After adjusting zoom, the image may become blurry — use the focus ring to restore sharpness.
4. Make small incremental adjustments and check the live image in Pylon Viewer or EthoVision's camera preview after each change.
5. Once the full arena is visible and the image is sharp, tighten any locking screws on the rings if present to prevent accidental movement.
6. If the zoom ring alone cannot capture the full arena at the current mounting height, consider adjusting the camera mounting position (raise the camera higher to increase field of view coverage) or using a wider-angle lens.
7. After finalizing zoom and focus, recalibrate your arena in EthoVision XT before running experiments.