Complex sentence: Indeed, it is very relaxed by the standards of any Dutch portrait, comparable mainly with some by Hals, although it seems unlikely that in reality she wore such formal clothes when painting in oils, especially the very wide lace collar.
Split into simpler sentences: Indeed, it is very relaxed by the standards of any Dutch portrait, comparable mainly with some by Hals. However it seems unlikely that in reality she wore such formal clothes when painting in oils, especially the very wide lace collar.