Traditional photoelectric techniques can achieve millimagnitude precision if a few simple rules are scrupulously followed. We illustrate the practical limits of differential photometry obtained with a dedicated telescope and photometer. Using a highly homogeneous set of measurements of bright F, G, and K solar analog stars, we present the distribution of observational noise and intrinsic stellar variability over a typical observing season and over the entire 8-year program. Finally, we list Strömgren uvby standards which we found to vary slightly.