How to Achieve Critically Sharp Photos - Examples

I have some questions regarding image sharpness that I would greatly appreciate help on. Here's the short version:

In photos such as Sardinia Man and Portrait of Steven Bellovin I see a kind of eye-popping sharpness that I _very_ rarely see, even in professional photographer's work. What are the most important factors in creating images with this kind of clarity? Could a Nikon D70 with one of Nikon's semi-pro lenses create a photo this sharp?

One of my primary reasons for buying a DSLR was to emulate this kind of incredible sharpness. Alas, after 2 years of taking photos (granted, mostly in fairly uncontrolled environments) I have yet to hit that mark. So after I came across this website's tutorial on image sharpness and its two constituents, acutance and resolution, I feel like I am almost ready to approach this problem again. However, I was wondering someone here could provide a little more insight.

Does such sharpness require a tripod? Are there any post processing techniques that are required?

The two photos you mention have a nice detail-enhancing cross light, which is one reason they look the way they do.

On the other hand, sharpness in a photo as small as these is often more dependent on the downsizing and sharpening technique than the original equipment. After downsizing the image, try using an unsharp mask with a radius of 0.2 and percentage of 200-400 and you ought to achieve similar results. This is discussed on this website's page about downsizing an image for the web and email. In addition, these images also have good micro or local contrast, which requires nearly zero lens flare. Make sure to use a lens hood, and a prime lens or high-end zoom to achieve good local contrast.

Having gradually improved my 'library' of lenses, based usually on buying the best (I can afford), I have noticed a marked improvement over the run of the mill lenses.

Find the right type of light (not necessarily the obvious) and the success rate of quality shots shoots up dramatically.

You might like to check out Photodo and see if you can find the MTF values for the lenses you currently own. You'll find an explanation of the ratings used as well, but simple relative MTF comparisons may perhaps help you see one very significant reason your images are not as sharp as other's. Case in point: the lens your first linked image was taken with, the Canon EF 70-200mm f/4 L, is renown for it's critical sharpness. That's a very good start.

I cant help thinking that the photographer's eye and skill also has a good deal to do with it. The composition draws the eye and the sharpness helps it to stand out as a memorable image.

The shot of the old man from Sardinia was a striking example. It reminded me strongly of how I saw things as a child - in critically sharp detail.