Comparison of strategies for background subtraction in NIRSpec/MSA observations. Left (red): Standard three-point nodding strategy, in which the galaxy is observed in three positions within the shutter, and the background for each position is estimated using the corresponding shutter exposures from the other two nods. Centre (blue): Nod2 strategy, a two-position scheme where only two out of the three available positions are used for the nodding procedure in order to use the shutters farthest from the galaxy as the background. Right (magenta): Local subtraction approach, which uses the outer shutters from the two off-source positions (indicated by the filled-in shutters) to estimate the sky background. In this method, the object signal is taken from the sum of all three nod positions (connected by dashed magenta lines), but no background is subtracted from the same shutters. As such, this method can be more sensitive to local systematics or background gradients.