Canon 312 XL-S - Manual (Page 28)

Shutter Release Lever
After setting the main switch to “R", depress the
shutter release lever to start shooting. This shutter
release lever has two steps. The first step is for light
metering and sound monitoring, the second for
filming.
Viewfinder
The viewfinder contains all information necessary
for shooting, such as the recording level indicator
at the top, the battery check/film end warning lamp
on the right and the film transport indicator below.
An underexposure warning mark in the lower right
corner and macro indication in the upper left corner
are also included.
Framing
Since the viewfinder has no parallax, the viewfinder
image is the same as the film image.
You can change the subject's size either by moving
closer to or away from the subject or by zooming.
Zooming
As the zooming lever is rotated, the size of the
image in the viewfinder will continuously change
while the focus stays the same. This is called
"zooming", and the change in magnification results