High spatial resolution capabilities of Doppler measurements with the Pic du Midi MSDP spectrograph

Abstract
We analyse observations in the NaD1 line (λ 5896 Å) obtained with the MSDP spectrograph of the Turret Dome of the Pic du Midi Observatory. Individual images reveal high spatial resolution and the data reduction shows the high capabilities of the spectrograph to get doppler measurements up to the limit of the resolution of the refractor (03). Dopplershifts are obtained in the middle and high photosphere. The smallest granules 04 show upward motions in the middle photosphere.