Abstract: A fixture for supporting objects for holographic testing comprises by two plates (11,12) which are attached rigidly and permanently to one another and of which, when the fixture is placed on a horizontal support surface, a first plate (11) will form a relatively small angle with a vertical plane, which angle will be substantially different from 0.degree., whereas the second plate (12) will form a relatively large angle (.beta.) with a vertical plane, which angle will be substantially different from 90.degree.. The plates are provided with holes (121,122) for receiving pegs for supporting abutment with an object.

Abstract: A method for monitoring a product under manufacture for possible deformation or changes in shape. In accordance with the method there is produced at given time intervals a series of halographic product images from which the rate at which possible changes in deformation take place in time can be estimated or evaluated. These estimated values relating to the rate of deformation and the rate of progressive changes therein are extrapolated so as to obtain the final value of the deformation of the product in relation to the state or form of the product immediately subsequent to the time of its manufacture. The process of manufacture is controlled on the basis of this final value, and the product is preferably cooled forcibly prior to producing the series of images.