Focus problems

I hadn't used my 50-150mm 2.8 since the first of the year . At that time , it was working fine . But I took it out the other day and now it seems to be off . It seems to be front and back focusing, Other times , I can't tell what the heck it's doing ! In other words , it's all over the place .

I think the warranty runs out this month , I'll have to check . Tomorrow I'll mount it on a tripod and check it out more . I'll also clean the contacts

But I can't figure out how a lens can go from working great to this . Surely lack of use is not the cause. Any thoughts ?

Have that problem too. On a 7D after micro focus adjust, it looks like certain focal lengths just won't focus properly but some do. Sigma gave me the bum's rush on the whole issue.

Still using the same camera??

yogestee wrote in post #11036403
Still using the same camera??

Yes same body, my 30D.

Wasn't really happy with the results mounted on the tripod today , either. Not what I'm use to , from this lens.

Now it's back to normal . I still don't know what caused the problem . I guess i'll keep using it and see what happens.

CountryBoy wrote in post #11049337
Now it's back to normal . I still don't know what caused the problem . I guess i'll keep using it and see what happens.

Can I send you mine so you can apply your healing powers to it?

JackProton wrote in post #11051152
Can I send you mine so you can apply your healing powers to it?

Sure . If I only knew what I did .