Thanks a lot for your attention. For the last 4 years I have been using Digital Cinema Desktop - Raw in After Effects. That option was available after installing Final Cut, but it has disapear in one of my computers. It never happened to be available in it anyway.
I have search trough the forum and I have found out that this option is available after Final Cut installing DesktopVideoOut.component in ~/Libary/Quicktime. I have found that component in all my computers, also in the one I am having trouble with.
This computer is a new mac mini -never used this very model before- running Mavericks -I have a iMac running Mavericks and it handles Digital Cinema Desktop with no problems- and using After Effects CS6 -at least 4 of my computers runs AE 11.04.2 with no problems.
I am a bit reluctant to belive that is the computer model -mac mini- the source of the problem.
Do you have any ideas?