QUOTE(Kidz1995 @ Apr 14 2010, 12:09 AM)
i still newbie in DSLR.
what do you mean by full frame lens ?
is it prime lens like Nikkor 50mm f/1.8 ?
p/s..can i request pic captured by these items to see the difference

refer
here for some info..
i think what the author was trying to say was that, if u use a DX lens on a FX/full frame camera, it would use a smaller portion of it's sensor due to the lens nature.
QUOTE(from the link posted above)
DX lenses don't work as well on FX cameras as they work on DX cameras simply because the FX cameras work at lower resolutions. A 12MP FX camera only uses 5MP when it uses the central DX portion of its sensor, while even the cheapest DX D40 has 6 MP in its DX sensor.
The FX D3 is the fastest Nikon ever when shot in DX, but its resolution isn't as high as cheaper DX cameras.
another interesting fact:
QUOTE(also from the link above)
-Canon's full-frame cameras aren't smart enough and can't use Canon's EF-S lenses designed for their 1.6x cameras.
-Unlike Canon, who dumpstered all its previous lenses when Canon changed its lens mount in 1985, almost all of the over 40 million Nikkor lenses Nikon has made in the past 50 years work to some extent on every camera.