CANONSCHOOL
86 http://www.digitalcameraworld.com
When do you use
the lock switch
on the Canon
EOS 5D Mark III?
Shannon Rouse,
BarmouthBRIAN SAYS... The lock
switch is usually used to
stop the quick control dial
on the rear of the camera
from changing exposure
comp while the camera is
carried. It’s a multi-
function switch and can
also lock the main dial and
multi-controller to avoid
changes to settings while
the camera is switched on.When you fit a
battery grip, what
do you do with
the battery door
that is removed?
Oliver Morgan, PlymouthBRIAN SAYS... Each of
the Canon battery grips
has a space to store the
camera battery door in the
grip itself. There’s a place
in the section of the grip
that goes in to the battery
chamber of your camera.My camera will
take photos and
display them on
the LCD without
a card inside, is
this normal?
Charlie Ellis, LudlowBRIAN SAYS... Ye s i t ’s
normal, but you can turn
this off. It’s set this way be
default so that cameras
can be demonstrated
in-store without a memory
card inside. However the
demo mode should be
turned off to avoid you
taking photos without a
card inside of the camera.
In the menus, disable the
release shutter without a
card option.My EOS 5D Mark IV has two settings
ALL-I and IPB for each movie resolutionand frame rate, which is best?
Tim Withington, HuntingdonBRIAN SAYS... The settings ALL-I and IPB determine how
single frames are stored in your movie file. ALL-I stores a
complete image for each, making the files larger, but since
each frame is complete, you require less power to edit.
IPB stores a key frame, every ½ second, and then only
changed information is stored for successive frames, until
the next key frame. This means smaller files, but when you’re
editing your movie, the computer may often need to
regenerate individual frames by going back to the key frame
and the creating the subsequent images that only partial
information was stored for.ALL-I compression creates larger sized video files than IPB,
but requires less computing power when editing your movieW hen is a cu s t om w hi t e
balance setting needed?
Robin Dean, KendalBRIAN SAYS... Custom white balance
is for when you need accurate or
consistent colours in your photos. In
Auto White Balance, the WB is set by
the camera using the colour info. If you
change the colour of one part in a
scene, then the whole scene may
change colour with AWB and most
preset white balances. To use a custom
white balance you need to shoot
something that is neutral in the same
light as your subject, a grey card, or a
sheet of white paper will work too.Photograph a neutral grey card then use the
camera menu to set a custom white balanceThe outer ring on the 77D adjusts exposure
compensation when you use program modeIs it always necessary to use a lens
protection filter, are there any times
you should avoid them?
Dave Clark, SwanseaBRIAN SAYS... Lens protection filters can be useful in
some situations, though I don’t use protection filters on
my lenses, except on a beach.
This is when you’re likely to
encounter windblown sand and
salt spray, so it’s a good idea to
use a protection filter. Though
you might be using a polarizer,
so that does the job for you. The
trouble is, inexpensive filters are
another layer of glass for light
to reflect off, and can reduce
sharpness and add flare.I just moved to Program,
why are my exposures soerratic with my EOS 77D?
Michelle Madeley, BridgnorthBRIAN SAYS... Program, especially
with Auto ISO works in much the same
way as Auto mode does on EOS
cameras. However with Program, your
camera activates the exposure comp
control linked to the quick control dial
on the rear of the camera. Auto and
Program can get good exposures, but
if the scene is very light, snow scenes,
you need to overexpose the metered
reading. For dark scenes, you need to
underexpose the metered reading.In windy conditions on a beach a
protection filter can be helpful to
stop salt water spray and sand