Hello zarbane,
I go through your problem you wrote, actually what i got is that you may need to use settings according to conditions and pictures you are going to capture.
Auto settings works mostly but settings provided for user are if you are not getting your required result. as you may aware these settings also have their own pre configured ISO, shutter speet etc effects which also greatly effects quality. hope you got some thing, Thanks.
captured this picture in full darkness using flash light only.
http://www.surgicalinstruments.cmxd....uredindark.JPG