Measured MIRI/LRS transmission spectra of K2-18b using a range of fixed channel sizes (1–8 pixel wide bins) and starting wavelengths (i.e., pixel shifts). The unbinned spectrum (panel (a)) exhibits significant scatter between adjacent channels, with a mean absolute difference of 663 ppm. For reference, the typical feature size in Figure 1 is ∼250 ppm. The scatter in the measured spectrum is seen to decrease with larger channel sizes and an even number of pixel rows (panels (b)–(h)).