Applescript and QT

Actually, I was able to find an Automator's script and to modify it so that it would do what I want. If it can be helpful for somebody, here's the Applescript code I created:

on run {input, parameters}
-- retropalette video recorder to hard disk
tell application "Finder" to activate
tell application "QuickTime Player"
new movie recording
start first recording
end tell
delay 8100
tell application "QuickTime Player"
stop first recording
end tell
return input
end run

Be advised that the "8100" is the lenght of the recording session in seconds, 2h15 in my situation.