new signma 70-200 f2.8 help please?

[donny1]

Hi,

i just got my new sigma 70-200f2.8 and i think it may be be a little soft. can some please help. i have conducted a rudimentary test. both images were shot from a tripod at the same distance to the wall at iso 400 using autofocus in ap mode with no flash


img_1705 is shot at f2.8
img_1706 is shot at f4


am i being picky, i have read a few reviews with people saying they have had bad lenses, i hope i am not one of them.

when i zoom to 100% in microsoft picture manager img 1706 looks sharper, give that it was shot against a flat surface i am guessing the dof should,t be too much of an issue? please help?

[OsmosisStudios]

Take a look at Sigma's widget:
APS-C
Full-Frame

Going off your example I'm going to assume 200mm f/2.8 and 200mm f/4. The difference in centre sharpness between the two is about what you show. Things never really sharpen up much past that on that lens, at 200mm. The sweet spot is 100 @ 5.6.

That's all assuming an APS-C sensor.

On full-frame, it's much better from the centre at f/2.8 and actually softens a bit at f/4. Sweetspot is more-or-less around 70mm f/5.6

[donny1]

Hi, you are correct, they were shot at 200. people have taken some nice shots with this make of lense, i am hoping to do the same.