Assessment of covariance introduced during KCWI-DRP cube construction using the representative pre-coadd J0910b exposure kb231212_00128_icubes.wc.c.sky.sky2.fits. The left panels show the distribution of blank-sky SNR values after progressive spatial binning from the native sampling to 6 × 6 spatial bins. The right panels show the corresponding distributions after progressive spectral binning from the native sampling to 6 pixel spectral bins. The solid black curve shows the Gaussian distribution expected for uncorrelated noise (μ = 0, σ = 1), while the dashed black curve shows the best-fitting Gaussian to the measured SNR distribution. Only modest broadening is observed with increasing bin size, indicating that covariance introduced by the KCWI-DRP geometric rectification and DAR correction is weak and largely confined to neighboring pixels.