Thank you for sharing your concern. Let me recommend some steps to further isolate and determine what you are experiencing. Please be aware that device speeds may vary based on multiple outside factors.
1) Check the Picture size (Camera Capacity) in camera setting (It should be Max according to Camera Capacity)
2) Turn on the Auto Flash (If Available in the Device)
3) Reset the Camera (From the Camera Setting)
4) Software update via FOTA,Kies or SMART Tool. Be sure to hit ♡ when you find an answer that works for you.