Observability and UV coverage

Abstract
Observing with an optical stellar interferometer is more complicated than observing with a single dish telescope. Several "hardware" constraints are added, such as the optical path difference compensation with delay lines as well as possible telescope vignetting. A more fundamental constraint is the coverage of the uv-plane. Its sampling costs a lot of observing time and thus should be optimized for each scientific source. These issues will be addressed in this tutorial and in Exercize number 2.