If you are using the "Auto" or "Auto Exposure" feature of the camera, then the camera's internal sensors need to be looked at by a professional repair shop.
If you are adjusting the settings yourself, my suggestion is to use an exposure mode of ISO 200 to ISO 800, keeping in mind the lower the ISO number, the more light you will need in the background, the higher the ISO the less light you will need.
You can take a learning class online or purchase a book about techniques of photography.
Answers & Comments
If you are using the "Auto" or "Auto Exposure" feature of the camera, then the camera's internal sensors need to be looked at by a professional repair shop.
If you are adjusting the settings yourself, my suggestion is to use an exposure mode of ISO 200 to ISO 800, keeping in mind the lower the ISO number, the more light you will need in the background, the higher the ISO the less light you will need.
You can take a learning class online or purchase a book about techniques of photography.
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