Is the Sigma 50mm F2 DG DN Contemporary Lens sharp? This page visually answers that question. Shown above are 100% crops from a lab-captured 50mm f/2.2 test image. Observe the contrast and resolution of these results.
Is the Sigma 50mm F2 DG DN Contemporary Lens set to 50mm f/2.2 sharper than the Sigma 65mm F2 DG DN Contemporary Lens set to 65mm f/2.0? The image quality comparison above also answers that question. Switch between the results to see the sharpness differences between these lenses.