Sharpness? resolution? contrast?

As you know, I was having some focus problems, so I did some test shots.
It was then that I realized that the Takumar 135mm F2.5 Bayonet gave better results that the Tamron 24-135mm at 135mm.
Takumar 135mm F2.5 Bayonet, ISO100, F4, 1/160, ~200% crop
[IMG]http://farm3.static.flickr.com/2702/4503747628_d402288e22_o.jpg[/IMG]

Tamron, ISO100, F4, 1/160, ~200%
[IMG]http://farm3.static.flickr.com/2791/4503118161_d108536a4b_o.jpg[/IMG]

My reaction was to say that the Pentax is sharper, but that isn't really the case.
There is no discernible difference in ability to resolve shapes and the lines that distinguish them. That is at least for regions with very different colours.
Because you can see the Pentax can give more detail overall, like in the bottom part of the tower were that is very clear.

But my question is, what property is this? Sharpness? Is it contrast?
The exposure parameters are equal but the image is darker for the Tamron, poor hability to resolve detail in shadows?

There seems to be lower resolution (the ability to record fine detail) in the Tamron image. To be sure though the Tamron shot needs lightening slightly.

What property of the lens defines resolution?
What I can see is two lenses that can direct the light so that the same item is described by the same pixels. At least the demarcation between contrasting areas seems to be well done on both.
But for the same pixels one lens can display more information than the other.

Its strange it seems a property of the sensor not lens , but here sensor is the same...

Resolution is the ability of the lens to resolve small details, not sure if this the scientific definition, it's basically the sharpness of the lens.

The Takamur appears to be more translucent, what happens when you've both photos at the same brightness?

Actually sharpness and resolution are totally different things. It is possible to have high resolution but low sharpness, simply because the details are resolved with low contrast. Alternatively, a very contrasty low resolution image can be sharp.