The gridded estimated bandpass error of the observation. The absolute values of the errors are taken and averaged across the frequency channels for visualization. Errors are estimated with two methods: “ValErr” and “SmoothErr” (discussed in Section 2.2). The left panels show the results for the z = 0.32 bin, and the right panels show the results for z = 0.44. The red circles correspond to the ∣u∣ < 2000λ region, where the visibilites are used for the power spectrum estimation.