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The thermal shroud of a thermal vacuum chamber is in most cases not perfectly closed. There are holes for windows and feedthroughs and some stands inside the shroud which influence the thermal behavior of the test article. Size and thermo- optical properties of the covers of the holes determine the effect on the temperature change of the test article. This influence is investigated for different cases as they occur in a thermal test chamber. Covers made of aluminized or black KAPTON and painted metal sheets are investigated. Mechanical fixtures are needed for installation of the test articles. By constraints of the test setup these fixtures often can't be designed as adiabatic or actively temperature controlled. For the case of large test articles with relatively low thermal heat capacity as reflectors for telecommunication satellites, the influence of the fixture on the final temperature is discussed for different cases and an optimized solution is presented.

The standard method of the application of videogrammetry during space simulation tests will be summarized. Some improvements, test setups and solved problems will be described. For a videogrammetry measurement a number of pictures are needed. The different views of the test article can be achieved by several methods Test setups with a rotating reflector or a camera on a rotating arm will be presented. If the distortion of the front and the rear side has to be measured simultaneously, two cameras one with view from the top side and an other with view from the bottom side was used. The tilt of the mounting interface with respect to the shell can be measured by means of an additional sophisticated structure attached to the rear interface. Special precaution has to be taken to reach the extreme temperatures in a reasonable time and with modest effort. A number of tests were performed.