There are two approaches to determining the thickness of a carbon film evaporated onto a specimen. One approach is to do the evaporation first and to measure the result afterwards. There are several ways to do this. The second approach is to put down a determined amount of carbon in the first place. This clearly has advantages in many cases. The method described here is of this second kind. The thickness of the carbon coating is not measured, but by a predetermined recipe, the amount put on is controlled at the time of evaporation, In principle, the thickness could be measured during the evaporation with a quartz-crystal thickness monitor. However, we find that the monitor we have does not work well with carbon.