Knowledge Base

Experiment Settings

Video Source: Live tracking

For Merged camera view, select 1280 x 1024.

Number of Arenas:

Arena Settings

Put the tracking chamber on the backlight unit.

Draw the two arenas.

Important: Right-click in the Arena Settings window and

Trial Control Settings

Remove the condition box between the Start-stop trial and Start track.

Detection Settings

Main Settings:

• Method: Dynamic Subtraction
• Subject: Darker than background
• Track Noise Reduction: Off

Acquisition

Select Save Video. Release the animal in the test arena, and click Start Trial.

To stop recording, click Stop Trial.

Analysis > Export Raw Data

Export Raw Data (Track and dependent variables, File type = Excel).

• For each trial, one file is exported (…….Trial [n].xlsx).
• Each file contains data for both cameras (Arena 1 and 2).

For each Excel file:

1. Rename it by adding Cam1 (this file has Arena 1 in the first sheet).
2. Make a copy and rename this copy by adding Cam2. In this copy, put the sheet of Arena 2 in front.

Track3D

1. Adjust the settings (interpolation, filters, 3D zones etc.).
2. Select New Calibration, then click Start Calculations; select the calibration file calibration_edited… (see the next page).
3. Select the first file from Camera 1, then the file for Camera 2.
4. Give a name to the results file (*.xlsx).

The 3D track chart appears. For the next trial, select Old Calibration.

For more information, see:

• The EthoVision XT Help
• The Track3D Reference Manual

Calibration

Do calibration only once, or whenever you change the position of the cameras relative to the test arena. The test arena must be exactly in the same position as when you record the animals.

1. EthoVision XT

1. Put the calibration frame in the test arena.
2. Make a new Arena Settings and rename it to Calibration.
3. Click Grab Background Image, then Grab.
4. Go to the Bitmap Files folder in your EthoVision experiment folder and copy the newest background.bmp file to the location of your choice (e.g. D:\calibrations).
5. Rename this file, for example Calibration image.bmp.

2. Paint.NET

Optional: Open the Calibration image. Choose Adjustments > Brightness/Contrast. Adjust the values to increase the white/black contrast.

Save the picture as Calibration_edited.bmp.

3. CentroidFinder

1. Import the Calibration_edited.bmp image twice.
2. Click the markers, first for Camera 1, then Camera 2. Follow the same order as in your calibration reference file.
3. The calibration file is saved (default name is Calibration_edited_date_time.xls).
4. Copy the coordinates from your Calibration reference file to this Calibration file.

For details, see the Track3D Reference Manual.

Source: Track3D 2 - Video Recording with EthoVision XT, Noldus Information Technology