While DNG uses JPEG XL internally for great compression, its implementation sacrifices some of JPEG XL's inherent advantages. For instance, JPEG XL's progressi

While DNG uses JPEG XL internally for great compression, its implementation sacrifices some of JPEG XL's inherent advantages. For instance, JPEG XL's progressive rendering and preview capabilities are lost within the DNG container. Additionally, JPEG XL's lack of frame boundaries (it has consistent filtering defined over all frame/tile boundaries -- being the only image codec that gets this right!!), is negated when used in DNG's tiled structure. This tiling introduces frame boundary artifacts at lower quality levels, similar to how other codecs behave in tiled contexts. Although these are minor issues, a pure JPEG XL implementation would offer superior progressive display, previewing, and artifact-free compression compared to the DNG-wrapped version.