ONE WAY to open up shadow detail without seeing excessive noise is to take a series of pictures from the same position, varying the exposure each time. Later, you can combine the well exposed areas of each picture in Photoshop or other layer-based photo editing software.
You can enable your EOS camera’s Auto Exposure Bracketing (AEB) function to take three shots automatically for you. It will initially record a standard exposure, followed by an underexposed version