We propose for method the evaluating astronomical climate characteristics the Baikal Astrophysical Observatory (BAO) by computer analysis of images obtained by the chromospheric telescope for solar full-disk. The modified file computer algorithm of the «optimal window» for the measure the image quality was applied. The processing was made of a large body data was made in automatic mode on hardware-in-the-loop complex which developed in V. E. Zuev Atmospheric Optical Institute of the Siberian Branch RAS on the basis of the parallel programming technology. The results of statistical analysis of solar chromospheric H – alpha filtergrams, which obtained in BAO in 2001–2002 by Princeton Instruments 2048B digital camera, are presented.