20 minutes exposure, Kodak Elitechrome 400 slide film.
5" f/5 refractor at prime focus.
NGC 7142 is a small, but rich cluster of faint stars in Cepheus, about 5 degrees south of beta cephii. Since it is a small cluster, moderate magnification will give the best view. The brightest stars are around 10th magnitude, so a 4" telescope is needed to show the individual stars in the cluster.