Set the tent up in your backyard,  pick a manual power setting on your flash. I chose ¼ power. Then with the camera on a tripod, I shoot a test exposure at f/4, f/5.6, f/8, f/11, f/16.  I then determine which f/stop is the best tent exposure, lets say f/8, and whenever I take that tent out, I know that the exposure will be f/8 with the flash at ¼ power in that tent. You then bracket your shutter speed during the shoot to get some darker and some lighter. The content you are trying to access is only available to members. Sorry.

Author