You are misinformed. The "conversion" of 2D movies into 3D is something that has only recently been possible. It has not been done for decades. Until recently, 3-D movies were shot in 3-D D, and most still are, thought this post conversion is unfortunately happenening now too. CLASH was shot flat, and then converted to 3-D in a rush at the last minute, which is why it looked so bad. The hope is, that they will use 3-D cameras in production for the sequel, and not use computer software to convert flat footage in post. AVATAR, MY BLOODY VALENTINE, FINAL DESTINATION, JOURNEY TO THE CENTER OF THE EARTH, RESIDENT EVIL AFTERLIFE, etc (as well all 3-D movies made for decades) were all shot with 3-D cameras; while stuff like CLASH, THE LAST AIRBENDER, etc were shot flat and converted. There are also some movies that have been shot flat with conversion in mind all along, such as PIRANHA 3D and ALICE IN WONDERLAND, but that's just because the directors were afraid of using a 3-D camera. Hopefully that will change, and they will learn how to do it right, because the final result is far superior. In other words, if you want to release in 3-D, shoot in 3-D, the traditional way, and stay away from the new "conversion" techniques.