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Hα filtergrams of selected active regions are obtained by the six inch refractor telescope at Udaipur Solar Observatory through a birefringent filter of 0.5 Å full width at half maximum. The field of view is ~4 × 5 arcmin with a spatial resolution of better than one arc sec. The filtergrams are obtained in the wavelength range of -1 to +1 Å centered at 6563 Å at steps of 0.1 ° A. A complete scan takes about 5 seconds (occasionally longer). The images are recorded with a cooled CCD camera and corrected for dark current and flat field. We observe the bright points in the filtergrams beyond 0.5 Å off line center. In general, these features are located away from the strong field regions. We study their property with respect to the co-temporal photospheric magnetograms obtained with the GONG instrument at Udaipur. This might help in understanding their relation with the magnetic flux emergence and annihilation.

We have observed about 15 active regions on the Sun, with the Advanced Stokes Polarimeter and Dick Dunn Telescope at NSO/SP to map the Stokes parameters in the photospheric Fe 6302.5 Å and chromospheric Mg I 5173 Å lines, during 1999-2002. The observations are corrected for dark current, gain, instrumental polarization and cross-talk using ASP pipeline. The wavelength calibration is carried out using the O2 telluric line 6302 Å which is also present in the observations. The photospheric and chromospheric longitudinal magnetograms are made from the Stokes V profiles, which were intercalibrated with the Kitt Peak magnetograms. The plasma motions are inferred from the line bisector measurements at different positions of the spectral line. In this paper we present the height dependence of Doppler velocity scatter plots of a sunspot in the photospheric Fe I 6302 Å line.