The reference signer's performance of the corpus was recorded first. His videos are thus called reference videos in the following. In order to ensure that all signers perform the same dialect, a reference video and its textual representation were prompted on a screen mounted below the camera. The reference video was shown once before recording started. After that the video vanished and only the text remained visible. When the camera started recording, the signer perfomed the prompted isolated sign or continuous sentence. If an error occurred, the recording was interrupted by the supervisor and the performance was repeated.