sorry this has taken so long to sort out but my wife gave birth last week to our new son and our priorities have been re-arranged somewhat!
anyway for people who are interested here is a small explanation of how to get exact camera data out of maya and into cinema 4d. this is pretty much one of those last resort kind of things (because it requires you to have maya anyway). my explanation kind of assumes that you already know how to use maya and cinema and just need a nudge in the right direction.
start out in maya and select the camera you need to export. at the top right of the screen click on the toggle to show the channel box/layer editor. choose file/export selection and show the export dialog. change to the export format to the .move format (this will create a basic tab delimited text file upon export). swipe over the channels you wish to include in your export, depending on the situation this would be the channels for translation, rotation and scale as well as the horizontal aperture width and focal length (as this defines the fov in cinema) and then click the ‘add from channels’ button in the export dialog to add these to your move file. aperture width and focal length have to be added manually to the list in the export dialog using the format of camerax.fl or camerax.hfa (you can see the correct extension to use if you click on the ‘channels’ menu in the channel box and choose channels/channel names/short). once you have finished adding the channels you wish to use you can click on export selection and save the move file. i tend to make sure i use a .txt extension for the file as most macs and pc’s will get mighty confused by the default .mov extension which generally belongs to quicktime).
the next step is to open the move file in a text editor (such as notepad on the pc or text wrangler on the mac) and then at the top of the file add in the names of the channels as tab delimited text. this isn’t entirely necessary but i like to do that so i can keep track of what the channels actually represent, so i will add in tx (tab) ty (tab) tz (tab) , etc. as the first line. save this altered text file.
now open up a copy of my cinecam template (i’ve attached this to this post) and select the null Raw camera data. from the plugins menu choose cinema 4d/ascii animation import and locate your move file. in the dialog that appears you will need to set headline to be checked (so the names you gave the channels are used as the names of the sequences created), separator is set to tab, track is set to real, and time is set to frame. press okay and cinema should tell you that it has succesfully imported the data. open the timeline and you should see that you now have tracks representing your camera data. you now need to drag them to the correct places (tx ty and tz should be dragged and dropped onto the X Y Z sequences of the null Camera_trans, rx ry and rz should be dragged to Camera_rot). should you have included it there is also a null for other camera data, position X being for focal length and position Y being for the horizontal aperture width. there is an xpresso expression that takes all this data and pipes it into the camera called shot_layout_v1. the xpresso expression compensates for the different orientation of the axes in maya and the fact that maya measures the aperture width in inches.
you should now have a camera that matches the camera in maya! you can now bake the shot shot_layout_v1camera so it becomes independant of the expresso set-up. finally you just have to remember to adjust your render settings to match the maya cameras aspect ratio.
cheers, simon w.