Canon EOS Rebel T5 User Manual page 157

ISO Speed During Manual Exposure Shooting
With [Auto], the ISO speed will be set automatically within ISO 100 -
ISO 6400.
You can set the ISO speed manually within ISO 100 - ISO 6400 in
whole-stop increments.
If [Z1:kHighlight tone priority] is set to [Enable], the ISO
speed will be ISO 200 - ISO 6400.
AE lock and autoexposure cannot be used.
Changing the shutter speed or aperture during movie shooting is not
recommended since the changes in the exposure will be recorded.
If you change the shutter speed while shooting under fluorescent or LED
lighting, image flicker may be recorded.
With ISO Auto, the movie shooting can record a suitable exposure even
when the ambient brightness changes.
By pressing the <B> button, you can display the histogram.
When shooting a movie of a moving subject, a shutter speed of 1/30 sec.
to 1/125 sec. is recommended. The faster the shutter speed, the less
smooth the subject's movement will look.
6 Focus and shoot the movie.
The procedure is the same as steps 2
and 3 for "Autoexposure Shooting"
(p.154).
k Shooting Movies
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