A1lex has provided us with this special option for those who are intersted in cropped video. It is now baptized as Frame to the Left:
Why would you be interested in this:
a. To frame your videos as close as possible to the center of the sensor.
b. To get extra writing speed in doing so.
Here is how to do it 5D3 compile de0bcff
1. Put your cam in video mode.
2. In Life View make sure your focusing box is centered by clicking in the joystick until the box is in the center. (Just in case you have moved it)
3. Center the subject and press 5X zoom
3. Press trash button and enter ML menu.
4. In Overlay tab set Global Draw to On, all modes.
5. In Movie tab enable RAW video, set your resolution, and scroll to Framing, select Force Left
6. Press Q and set your FPS Override if desired.
7. Press half shutter to go back to LV
8. Click the joystick two times to the left and center your subject.
9. Press record button
Note LV will only show in gray and not very smooth. This is correct but now note that the focusing box is showing you the center of the actual video that will be recorded.
The following pictures show the results of this setup. The purple shaded image is the frame and the total image represents the entire image from a photo of the setup. Not all resolutions have been shown.
Note the
X represents the center of the frame and it is very close to where the framing, via Global Draw, shows up on the LV screen.
Here is the 640x368 framing:

At 1280x720 it is almost centered:

Here is 1920x1088 is a bit to the right:

And the largest frame possible
