Why is there a black shadow when taking photos with Canon camera 100d without flash?

When the ambient light is insufficient and the flash is not used to fill the light, it will cause underexposure and the photo may be a black shadow. In this case, try to use a flash to fill in the light. If you are not allowed to use a flash, you can use Av mode and a large aperture, and appropriately increase the ISO value to shoot. If the lens has anti-shake function, you need to turn on the anti-shake function of the lens. Due to insufficient light, the exposure time may be lengthened. A tripod should be used to stabilize the camera.

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