Signal in the convolved long-wavelength NIRCam cutouts is shown for our stacked UHR candidate sample, with insets corresponding to F277W (top left), F356W (top right), F410M (bottom left), and F444W (bottom right). The blue line represents the signal, in μJy, for each pixel in the stacked image as a function of its distance from the center of the cutout (measured in pixels). A dashed green line depicts the Gaussian fit used to estimate the aperture photometry radius, while a dashed red line indicates the mean background level. The vertical dashed blue lines mark the inferred radius for fiducial aperture photometry.