A Proposal for the Seeing Measurement of the Site Testing

A proposal for the measurement of the seeing is presented. A mask having three separate apertures, two of them with a 8" wedge each, is mounted on the front of the telescope tube. A 488×780 CCD camera is used to record the star trails of the three images for each exposure. The exposure time is about 1/30 sec. and the interval between the adjacent two exposures is about 0.06 sec. for separating the trails of each exposure on the CCD. After about one hundred exposures and when the trails fill the whole rows, the telescope is moved to locate the star trails at the beginning of the next several rows and then, the next exposure is carried out again. The geometrical centroid calculated tor each profile yields the differential motion of the images of the three apertures, its variation with time and the RMS image motion.