Knowledge Base

Problem

Users upgrading to EthoVision XT 19 want to use the new Focus Assist / calibration card feature but do not know how to obtain the calibration card or use it correctly.

Details

Introduced in EthoVision XT 19, the Focus Assist feature uses a printed calibration card to help users set camera focus and calibrate the arena. Some users assume the card must be physically shipped by Noldus, while it can actually be self-printed. Affects users upgrading from EthoVision XT 17 or earlier who are setting up new rigs with XT 19.

Solution

1. The Noldus Calibration Card does not need to be ordered — you can print it yourself on standard 8.5 × 11-inch paper.
2. Print the card at 'Actual Size' (do not scale to fit or shrink). After printing, verify the card's marked dimensions are correct: the two reference measurements on the card should be 4.8 cm and 7.9 cm. Measure them with a ruler to confirm accurate printing before use.
3. To use the card for Focus Assist / calibration:
a. Open EthoVision XT 19 and navigate to Arena Setup.
b. Select 'Grab Background Image.'
c. Place the calibration card flat inside the arena, ensuring the black rectangular outline on the card is clearly visible to the camera.
d. Select 'Calibrate.' EthoVision will attempt automatic detection of the card's outline.
4. If automatic detection fails, manually indicate the card's corners on the image as prompted.
5. Once calibration is complete, remove the card from the arena before proceeding with background capture and animal tracking.