... 1.2 Principal geometry of MASS/DIMM device . ... typ es of CCD camera used and in the construction of the mechanical interfaces for attachment of the instrument to the feeding telescop e. The next chapter is a guide for alignment of the optical scheme elements ­ the op eration which is mandatory after the device assembly or while installing the device on the telescop e. Exit pupil optics tuning ( MASS segmentator and DIMM mirrors ), fo cusing and lateral p ositioning of the Fabry ...