High dispersion spectra (0.2 A/mm) were taken during the passage of one sunspot across the solar disk, for simultaneous micrometer and photometric investigations of a sunspot velocity field. The Fe I line at λ 5576 was selected for the investigation because it is unaffected by the sunspot magnetic field (Landé splitting factor g = 0). From detailed micrometer measures, solutions have been attempted for umbral and penumbral velocity components. The photometric analysis is based on a determination of the line contour λ 5576 across the sunspot for three disk positions. An attempt is made to relate the penumbral line asymmetry (line-flare) with visual measures of the line shift. The micrometer measurements show that the umbral motion is characterized by a small vertical velocity of descent (0.1 km/sec −1 ), while the predominantly radial, penumbral velocity field pattern appears to be both flattened and broadened during the passage of the spot from centre to limb. From the photometric measurements it is found that the line asymmetry is greatest at approximately the position of the maximum sight-line velocity within the spot, and appears more pronounced for spot positions nearer the solar limb. It is clear that in visual sunspot measures the eye does not set on the line-core but at a point towards the penumbral line-flare. The equivalent width of λ 5576 shows a marked increase from the photosphere to sunspot. The central intensity of the line within the spot increases with distance from the spot centre.