Canon 814XL-S - Manual (Page 119)

1. Point the camera at the subject, and move
close enough to fill the viewfinder with the
subject.
2. Push the release button in the center of the
exposure control dial, and rotate the dial
clockwise to position at MANUAL. The
manual aperture warning lamp will light up in
the viewfinder to remind you that the camera
is not in the AE mode.
3. The aperture control lever, inoperative in all
modes but MANUAL, can then be moved up
to O to open the iris diaphragm or down to O
to close the diaphragm, giving you the aper­
ture value that you need
while pressing the
shutter release lever halfway.
4. Check the aperture indication in the view­
finder, and release the aperture control lever
when the viewfinder shows the desired f-stop.
The exposure value is retained by the camera
when you begin filming, and will be held until
the exposure control dial is moved to the
AUTO position or until you push the aperture
control lever again.