What I do before buying, copy a movie with many dark scene, a movies with fast scene ( day or night) and a movies which are colourful on a thumdrive. Make sure the movie quality is good say 1080 quality. At the shop, I request the sales guy to set the TV to factory std and then plug in the thumbdrive and test the movies on the TV. Finally I end up with Panasonic 55inch 4K smart TV.