Sekonic L-558R / Nikon D200 Exposure Test 1

I've been using my Sekonic L-558R to set the exposure for my Nikon D200. So far I seem to be habitually underexposing the images more than I'd like. Above is a Gretagmacbeth grayscale card exposed as indicated by my meter in incident mode. I have included histograms in the images.

The same scene with the camera opened up 1/3 of an f-stop.

2/3 of an f-stop brighter.

At a full f-stop brighter the white on the card, which is supposed to be at something under 94% reflective, is off the histogram.