Here are tests images that show the resolution capabilities of the Tamron 180mm f3.5 Di Macro. These samples are center and left edge 100% crops from the 10MP Nikon D200 (which has an APS-C sized sensor), and is equivalent to looking at prints greater than 3 feet wide.

These test images only reflect resolution; other lens shortcomings such as light falloff, chromatic aberrations, field curvature and flare and ghosting are not considered here.

It appears that this lens out-resolves the 10MP D200 sensor in the f5 to f9 range. The sharpness holds up well to about f11 when diffraction starts to be the major limitation.

The bottom row has 100% center crops from the Nikon 50mm f1.8 AF-D taken at f4. The Nikon 50mm f1.8 AF-D at f4 out resolves the 10 MP D200 sensor and the samples are only for comparison purposes. Ignore any slight differences in exposure or white balance.

f3.5 center

f4 center

f5.6 center

f8 center

f11 center

f16 center

f22 center

f3.5 edge

f4 edge

f5.6 edge

f8 edge

f11 edge

f16 edge

f22 edge

50mm f1.8 at f4

50mm f1.8 at f4

50mm f1.8 at f4

50mm f1.8 at f4

50mm f1.8 at f4

50mm f1.8 at f4

50mm f1.8 at f4