Distribution of the different spectroscopic and lensing samples used in this work. The plot on the left shows the North Galactic Cap (NGC), where most UNIONS galaxies lie. On the right is a portion of the South Galactic Cap (SGC), with the DES Y3 observations in the most southern part. There is no overlap between the UNIONS and DES Y3 catalogues. The apparent variation in shades between the two panels is due to the two projections resulting in different point densities.