Color–color diagram of the NIR data from Meingast et al. (2016) for different magnitudes limits. The red ellipses are the covariance estimates drawn for one, two, and three standard deviations. We find a relatively small distribution width for the typical 2MASS magnitude limit at K_S ~ 14.5 mag in both axes which allows for an efficient description of intrinsic colors via a mean and covariance estimate. By increasing the magnitude limit, galaxies at H−K_S ~ 0.7, J−H ~ 0.8 mag significantly broaden the distribution and introduce a large statistical error when estimating intrinsic colors with a single averaged value. Also very well visible is the shift of the mean intrinsic color (i.e., the center of the ellipse) even beyond the M-branch of the stellar main sequence toward galaxies.