If I wrote this book, I'd be very upset with how it was handled.

Rating: 2/10 (18 October 2015)

The author Andy Weir must be very upset with how his incredible book was watered down from a survival story to a vacation on Mars. Since he had no creative control, we can only blame Drew Goddard (screenplay) and Ridley Scott (director).
The book is filled with science, math, intelligence, problem solving, tension, obstacles, survival and wise-ass remarks. Sadly, they decided to keep in the wise-ass comments and cut the rest.
The movie feels like the main character is on a 2 year vacation on Mars, rather than fighting for his life and struggling to survive, like in the book. Day after day, he just waits to be rescued, without having to overcome much. This is my main problem with this film. They removed mostly all of the obstacles that Mark had to overcome to survive, and just glossed over what he did overcome. These obstacles demonstrate the intelligence and resolve of the character, all which is lost in the film. Removing the obstacles also removes the tension, which the book had plenty of.
Here are some major obstacles that were in the book and not in the movie:
-Mark accidentally destroys the Pathfinder communications while drilling holes in the Rover roof. This prevents him from communicating with NASA for his entire journey to the Aries IV site. He's completely in the dark. On his own, trying to prepare for the LONG trip. Keeping this in would have added suspension that the filmed lacked.
-While en route to the Aries IV site, Mark encounters a dust storm that delays his journey. The dust storm prevents the sun from recharging his Rover batteries via the solar panels. Mark has to figure out a way around the storm without dying, and also has time against him. He must avoid the storm and still make it to the Aries site before the MAV launches. This again would have added tension, conflict, and suspense. All missing from the film. In the film he just gets in his rover, and a few days later, arrives 3200km away, exactly where he needs to. It's lazy.
-Mark finally overcomes the storm, figures out a solution, and cheats death. Back on track, just as he's nearing the Aries IV site, he goes off a ridge and flips his rovers and almost dies again. He has to problem solve to get to the MAV site on time before the launch. This would have added more tension, more suspense...all which is lost in the film version.
-The book has Mark deploying a pop-up tent from the Rover Airlock to sleep in on his journey. The movie skips all of this, and instead show him sleeping under the rover...in the freezing mars atmosphere. It was interesting to me in the book how he crafted a custom tent for his bedroom for the journey.
-The book goes into detail on survival on a foreign planet, with numbers to back it up. It explains everything in the HAB, and what it's for. The film merely mentions a few key things, but never explains what they are for. Like how does he have enough oxygen to survive? How is he removing the CO2 from the air so that it doesn't reach toxic levels? This would have been great to show Mark figuring these out on screen in real time. Show how smart he is...that maybe he can get out of this if he puts his mind to it. All skipped. I can't believe they don't mention oxygen supply once. They assume if he's in a suit, he can breath.
"I'm going to have to science the s*** out of this." ... So much so that you won't even know he used any science at all..
What's so great in the book is how Mark is able to MacGyver everything, and overcome all of the obstacles that come in his way in order to survive. When you remove all of those obstacles, it just feels like Mark is waiting on another planet for his friends to pick him up. It loses all tension, all suspense...they took way too many shortcuts.
You may argue that time was an issue, and that is why those scenes were cut. Nah...I don't need the final celebration scenes in the movie, the post credit roll that highlights the actors, the final scene where Mark is an instructor. Cut all that out and put in the good stuff. The stuff that life is about...obstacles and overcoming them.
Bottom line, it's lazy, and doesn't do the book justice. If you want the real movie experience where you actually care about the characters and what's transpiring, listen to book.