Wide Angle focus issues (Sigma 10-20mm f3.5)

[timethief]

Hello Guys,

I bought the Sigma 10-20mm f3.5 just before going on vacation. I didn't have much time to read thoroughly into shooting with wide angle lenses (but i did my share of reading before buying it).
Anyway, seems to me that i am having focus and sharpness issues with this lens to the point that i have started doubting if there might be a manufacturing fault.

I am using the lens on my D90 and have found it very inconsistent to focus with the"Auto Focus".
I focus on the same subject and get various different values on the distance scale, although my focus point is the same in the shots.
I tried various different settings and its always the same.

Would appreciate some feedback

Thanks

Sem.

 

[Samanax]

Do you know anyone else with a Nikon body they can test your Sigma on? If the problem is repeated on their bodies then the lens might be defective.

Are you doing these focus tests in good light?

 

[timethief]

Do you know anyone else with a Nikon body they can test your Sigma on? If the problem is repeated on their bodies then the lens might be defective.

Are you doing these focus tests in good light?

Yes I tested in good light, outdoors with bright sunlight midday.
Would it make a huge difference with or without a CPL?

I have a D40 i can test it on. I will do that and see if it makes a difference.

Thank you Samanax.

 

[timethief]

Do you know anyone else with a Nikon body they can test your Sigma on? If the problem is repeated on their bodies then the lens might be defective.

Are you doing these focus tests in good light?

I took this lens to the service, and apparently there is a manufacturing fault.
They are replacing the lens in a few days time with a brand new one.
Service response was really quick.So at least I am happy with that.
I would have been really uneasy using this lens if they had repaired it.
I will test the new lens and see how it is.

Thanks Samanax.