The subject at 35mm (70 mm equivalent).

At 35 mm, from left to right: f/2, f/2.8, f/4, f/5.6, f/8. The difference in sharpness is very apparent. The best results are achieved at f/5.6.

At 60mm, from left to right: f/2, f/2.8, f/4, f/5.6, f/8. At f/2, the lens isn't very sharp. At f/2.8 and f/4, it's acceptable, and at f/5.6 and f/8, it’s pretty good.

At 100mm, from left to right: f/2, f/2.8, f/4, f/5.6, f/8. At f/2, I couldn’t take the shot, since 1/4000 s wasn't short enough. However, at 100 mm, the image is still noticeably worse at f/2.8 than at f/4 and on.

A shot at 35 mm.

At 35mm, from left to right: f/2, f/2.8, f/4, f/5.6, f/8. At f/2.8, in this case, the image quality is even worse than at f/2. However, there's no real sharpness anywhere at any aperture..

At 35mm, from left to right: f/11, f/16, f/22. At f/11, I still had a 1/125 shutter time At f/16 and f/22, I only had 1/60 and 1/30 s shutter times, respectively. Despite this only being a 35 mm focal length, the shots have camera-shake induced blur at 1/60 and 1/30 s shutter times. Holding this lens steady is very difficult.

A shot at 100mm.

At 100mm, from left to right: f/2, f/2.8, f/4, f/5.6, f/8. At f/2, the lens is noticeably softer.

100 mm and 1/125 seconds. It took a few tries to get a steady shot. With the weight distribution being the way it is, your hands start shaking quickly.

A shot at 35 mm.

At 35 mm, from left to right: f/2, f/2.8, f/4, f/5.6, f/8. With near subjects, the lens performs a lot better at f/2.8 than with distant subjects. The elements inside the lens are in a different - and apparently better - position.

At 35mm, upper right corner, from left to right: f/2, f/2.8, f/4, f/5.6, f/8. This isn't about sharp or soft, it's about how the lens renders out of focus areas. A test of bokeh, to use a short term.

A shot at 35 mm.

35 mm, f/2, f/4, f/8. Focus was set to centre point, and as you can see, even in this point, at f/8, the sharpness is far better than with other apertures.

35 mm, f/2, f/4, f/8. Notice how the depth of field changes.

A shot with a near subject at 100 mm.

At 100mm, from left to right: f/2, f/2.8, f/4, f/5.6, f/8. At such close range, the differences are minor.

At 35 mm, 1.5 m subject distance, from left to right: f/2, f/2.8, f/4, f/5.6. Always test the lens at different distances. The lens configuration changes depending on subject distance, and this affects the image quality. This picture also shows that there are very minor differences. However, even under studio lighting, the lens had a bluish tint at f/2.

At 100mm, 3 m subject distance, from left to right: f/2, f/2.8, f/4, f/5.6.

At 70mm, 2m subject distance, from left to right: f/2, f/2.8, f/4, f/5.6. Again, with nearby subject, the image quality is very consistent.