Printing symbols on media is described. Sequential parts of a symbol are marked onto each of multiple corresponding sequential segments of the medium. A characteristic of each of the sequential symbol parts is evaluated. A speed is monitored with which the medium is moved upon the marking of each of the sequential symbol parts onto each of the corresponding sequential segments of the medium. An image, captured in relation to the evaluation, is adjusted based on the monitored speed. Adjusting the captured image may include setting a rate at which the evaluation of the characteristic of each of the sequential symbol parts is performed based on the monitored speed or alternatively, predicting a distortion in the evaluated characteristic of each of the sequential symbol parts corresponding to the monitored speed, and applying a change to the captured image corresponding to, and ameliorating the predicted distortion.