Lightning Thief Movie upsetting...?

Did anybody else think the movie was....stupid? it followed the book maybe 40% then took its own path. Luke had no visible scar, Luke used the lightning bolt as a sword, The lightning bolt was a power, not a bomb, Hades had no helm of darkness, Kronos was barely mentioned. There are many more things that happened. I unde3rstand directors changing things for a better audience, such as the age of the characters, but there wasnt even a Great Prophecy. It was a decent movie, and unless you read the book, you wont realize how much different it is, and how upsetting it is.