Sorry for the vague description.
It is out of focus, and 'the focused point' is obviously not clear.

Hi Everyone,

I am a new comer with a question. Recently I bought a used 43mm f1.9 online, and I found with this lens my auto-focus on K10D is not working very well but with my others like 16-45mm f4 it is all right. So I am wondering if there is a problem with this lens or this is normal for the combination K10D+43mm f1.9. Or other possible problems?

Thank you.
Peng