Lowering the brightness of the camera flash
This question was asked over at StackOverflow HERE

Basically, the answer is No. The OS is limited to pretty much just FLASH_ON and FLASH_OFF. Though I have seen some flashlight/torch apps that have a 'turbo' mode that makes the LED even brighter (but that's not what you want and these types of apps usually require ROOT access).

Another workaround is to remove the back cover, put a small piece of tissue paper over the LED (make sure the paper is still big enough to be held in place with the back-cover back on) and put the cover back on.