I have been taking shots of a fish tank while the light are off with the internal flash. I am trying to get my shutter speed up and keep the aperture at 1.4. In AV mode I cant keep the shutter speed fast at F1.4. When I put it on P mode it gives me a faster shutter speed at a set F2.8, but of course I cant change the F stop in this mode. This is with a constant ISO not auto ISO. I have tried in manual mode and its the same thing. I hardly ever use my flash so any help is greatly appreciated! Thanks Guys.