Canon EOS Rebel SL2 EOS 200D Instruction Manual page 416

Troubleshooting Guide
The standard exposure cannot be
obtained or the exposure is irregular.
During viewfinder shooting or Live View shooting, if you use a TS-E
lens (except the TS-E17mm f/4L or TS-E24mm f/3.5L II) and shift or tilt
the lens or use an extension tube, the standard exposure may not be
obtained or the exposure may be irregular.
The continuous shooting speed is slow.
The maximum continuous shooting speed may become slower
depending on the shutter speed, aperture, subject conditions,
brightness, lens, flash use, temperature, battery type, remaining
battery level, shooting function settings, etc. For details, see page 124.
The maximum burst during continuous shooting is lower.
If you shoot a subject that has fine detail such as a field of grass, the
file size will be larger, and the actual maximum burst may be lower
than the number listed on page 129.
ISO 100 cannot be set.
Under [54: Custom Functions(C.Fn)], if [4: Highlight tone priority]
is set to [1:Enable], ISO 100 cannot be set. If [0:Disable] is set, ISO
100 can be set (p.367). This also applies to movie shooting (p.239).
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