Once preview images are available Chart Flight notifies the respective user via e-mail. Such an e-mail contains among others a link to the preview web page of the job where users find snapshots of different states of their video. This preview mechanism provides a first overview of how the generated video will look like. Users can either modify the settings and re-render all images, confirm it for final rendering, or simply delete the job. While the rendering of preview images only takes seconds, the rendering of the video usually takes several hours, see Section 5. Again, when the rendered video becomes available ChartFlight sends a notification e-mail. Both generated and uploaded data is kept on our server for a fixed period of time (currently one month). Users access these data via