I've been suspicious of my Nikon D70's autofocus system lately. In low light, it's been consistently missing my targets. I finally decided to do a test using the chart at http://md.co.za/d70/focus21.pdf

Here's the result using room light (and the focus-assist light) with my camera on a tripod:



Looks like the camera is going back to Nikon for calibration. *sigh*