The EOS 5D Mark IV allows you to set an Auto ISO and also a lower limit shutter speed to ensure the shutter speed will not become too slow that it induces camera shake or subject blur. This is particularly useful when shooting in P or Av mode where the shutter speeds have free range of adjustment. When setting the Auto ISO speed range, you can also select the minimum shutter speed to ensure it never goes too slow. With this set, you may sometimes find the shutter speed drops below the lower limit you set. This is likely because the correct exposure could not be achieved within the Auto ISO range and with the lowest shutter speed you selected, so the shutter speed will be shifted to adjust. If you have to ensure the shutter speed does not change below a certain level, then you should set it manually instead.
- Camera settings
- EOS 5D Mark IV