What does the histo on the camera show when you preview them on the LCD? If it's reflecting the -1EV, then respect the histo and disregard the appearance of the preview itself.
Also, most photos with good contrast often benefit from a Levels operation in post, this is true even if you've lit the the scene sufficiently.
For this type of static photography, I would also look at your metering choices. Since you have the luxury of the subject not going anywhere, try spot-metering and CW to see if you get closer "out-of-camera" results.