Lens Sharpness CF vs FF

Hi,
I'm quite new to digital photography and frequently found some facts are totally opposite to my guess, well that's natural, right.
While searching for the nifty fifty, I ran across a test of sharpness for the same lens using on a ff body vs cf body.

http://www.dpreview.co​m …anon_50_1p4_c16​/page4.asp
http://www.dpreview.co​m …anon_50_1p4_c16​/page5.asp

While in the page, go to the apperature setting below the graph and drag it to find the sharpness when stop down.

Although they did explain due to the 1.6 crop sensor that cause the sharpness to appear so differently, I'm very confused. Here are the questions I have:
1) Since cf body use only the field in the center, wouldn't that gives the best sharpness area for cf?
2) If the sharpness is indeed caused by the sensor size, how would a lens fair out using on a 10mp cf vs a 16mp ff, given Canon's 1.6 crop?
3) I know many of you are very knowledgable about digital photography. If the sharpness caused by other factors, please feel free to post here.

If this issue has been beaten to death, my apologies for bringing it up again. I did not find such comparison while searching here.
Thanks.

vincent_su wrote in post #6873032
1) Since cf body use only the field in the center, wouldn't that gives the best sharpness area for cf?

True, the lens sharpness on the sensor is at its best near the center. The probem that CF has vs. FF is that the image has to be enlarged 1.6 times as much from sensor to print. This means the CF sensor has to resolve detail at 1.6X times smaller detail (forgive this horrible math statement) just to break even.

Don't forget that pixels are an area measure, so I don't think the 1.6X linear conversion is what you are looking for here. In any case, until the print size starts to ask for more than 250 linear pixels / printed inch the pixel count does not really matter.

Long answer is too long to give, but basically with the pixel counts available in any recent (less than 5 year old) dSLR and given prints under 20x30 you do not need to worry about pixel count much.

The biggest issue in sharpness is how much detail the lens can resolve on the sensor (this is lens quality) and then how much that detail has to be enlarged to make the print. So the critical factors are the best possible lenses combined with the largest format sensor that they can cover with their image circle.

These two factors are more important than the number of pixels, the number of bits and the name of the image processor.

Jeff,
Thanks so much for your quick reply. That pretty much answers my questions.