Evolution of the measured parameters during the 5 h sequence on GJ 15A. From bottom to top: airmass, image quality, amount of atmospheric water, S/N in the H band, RV FP drift, RVs (cyan for individual spectra, blue for polarimetric sequences), RVs per band (blue, green, orange, and red for Y, J, H, and K bands, respectively), d3υ, FWHM, chromatic slope, and longitudinal magnetic field.