# Important things to know about data acquisition

Four methods to acquire data

Choose the method that best suits your setup and experimental protocol:

▪Acquire data live. The animals are tracked as they move in your experimental setup.

The disadvantage of this method is that you do not have a video backup, so if you need to repeat data acquisition you have to repeat the test itself.

See Acquire a trial live or Acquire a series of trials - live.

▪Acquire data live and save video simultaneously. Like above, in addition EthoVision XT records video to a digital video file. You can use the video to re-do tracking if needed.

See Acquire a trial live + save video or Acquire a series of trials live + save video

▪Record video with EthoVision XT, then acquire data. This is a two-steps method. First, record video to a digital video file as the animals move in your experimental setup. Afterwards, open the video file and acquire the data. This way you are free to track data later. See also Advantages of using video files below.

See Record video, then acquire a trial, or Record a series of videos, then acquire a series of trials.

▪Acquire data from video files recorded with other programs. Use an external program, like MediaRecorder, to record video to a file while the animals move in the experimental setup. Later on, open the video file and acquire the data.

See Acquire a trial from a video file recorded with other programs, or Acquire a series of trials from video recorded with other programs.

See also Video file formats.

Advantages of using video files

▪You have a video backup. A video file is very handy since it allows you to acquire data for a trial once again, if needed. For example, if you realize that the detection settings were not optimal when you acquired the data. See Redo a trial

▪You make sure that tracking is reliable. When you track from a video file, let EthoVision XT take as much time as it needs to analyze each sample, independent of the actual frame rate. For example, if the detection method used requires a lot of time per sample, acquisition may be slower than real time, but you ensure that no sample is missed. See DDS (Detection determines speed)

Settings used for data acquisition

You can view which settings were used for a particular trial.

In the Experiment Explorer, click Trial List. Click the Show/Hide button on the toolbar and in the Show Variables window, select Arena Settings, Detection Settings and Trial Control Settings.

In the Experiment Explorer, settings profiles are marked with a lock icon, meaning that they cannot be edited. To edit a settings profile, make a copy.

To view your trials

Choose Setup > Trial List. Click the Show/Hide button on the toolbar. In the Show Variables window, select Acquisition status. For an explanation of Acquisition status, see System variables .

Correct tracking errors

Good detection settings do not generally result in tracking errors. Before editing tracks, make sure that the lighting conditions and the detection settings are optimized.

See Edit the Tracks