Micro Focus Adjustment help - Sigma 24-70 & 7D

[jdfotos]

Right, hoping one of you nice folks will give me a solution I havent tried....

Got a Sigma 24-70 2.8 HSM second hand the other day for a good price. Less then 1 year old, not a scratch on it. BUT..... I seem to be having focusing issues, so, ok, kinda knew I might have to MF adjust.

SOooo.....I adjust on my 7D so its lovely and sharp at wide and tele end.
Today I go out and shoot some pics of my daughter who was a way away, and when I look at the photos, they are soft. So Ive tried the MF again, and it seems that if I adjust so its sharp for close objects, its soft for distant objects.
And vice versa.

Anyone got any suggestions, I dont want to believe I've bought a lemon.

Should I send it back to Sigma for adjustment/calibration or something, or is this kind of difference normal, and Im just going to have to find a happy mid-ground?

Sorry for the essay.....

 

[arad85]

Try taking photos at a number of MA settings at a number of zoom settings. I thought my 24-105 was out and varied depending on zoom, when I tried it with real world photos, it wasn't...

 

[jdfotos]

Tried that again this morning, same result.... its either good for close up objects, or distant ones, not both at the same time :thumbsdown:
Oh....this is wide open by the way. Above f4 it seems fine.

Send it to Sigma?

 

[arad85]

Send it to Sigma?

I would - together with a detailed report of what you see (perhaps including some pictures on a CD with exif intact).