Published online by Cambridge University Press: 12 April 2016
the large field Lallemand electronographic camera has proved to be an ideal receptor for bidimensional photometry with the C.F.H. 3.6 m. Telescope. It permits to measure faint stars up to about B = 25. Plates of a large variety of objects have been obtained ; for example : crowded fields such as the nearby galaxy Messier 33 ; fields where one must recognize faint galaxies from stars; objects for which a high spatial resolution is needed, such as the optical jet of Messier 87 or gravitational lenses. It is possible to predict the limits of the receptor with a very large telescope.