• In 1973 A.Behr published an article where he described the effect of coma and proposed a method for aligning telescope optics. It appeared in Astron.Astrophys.28, 355-358 : "A proposal for the alignment of large telescopes"(°). Now it's known as the most sensitive test for telescope alignment in amateur telescopes.
• In 1980 R. Wilson described also the effect of astigmatism and spherical aberration and gave simple formulas based on geometrical optics to estimate these aberrations from the location of the shadows produced by the egde of the pupil and its central obscuration. It's a Memorandum of the ESO Telescope Project Division : "Procedures and formulae for the adjustment of telescopes and analysis of their performance" (°)
• Book about startesting telescopes by Harold D. Suiter where a method is described to quantify spherical aberration by applicating an artificial central obscuration and look at inside and outside "shadows" of it and measuring the distance of focus. It was published at Willmann-Bell.
• In 1988 F. Roddier showed that the defocused images contain information on both the wavefront and the wavefront-tilt. It has been used to test a lot of big telescopes and better their alignment. It's also the basis of their wavefront curvature sensing technique used for adaptive mirror steering ! It appeared in Appl. Opt. 27 1223-1225 : "Curvature sensing and compensation: a new concept in adaptive optics". (°)

Anyone that can help me getting more information  mailto:jvb@digilife.be

Works mentioned and followed by (°) are not yet in my possession and a copy of them is gratefully accepted !