New Lens - What just happened?

Ceistinne wrote:

bvy wrote:

I bought a used Sigma 50mm 1.4 DG HSM EX lens. It arrived today, and the glass and body look great. I slapped it on my SD15, powered it up, and it would not autofocus or take a picture. I checked all settings on the lens and camera, powered down/up, took the lens off, checked the contacts, remounted it, etc. No change.

I noticed the manual focus had some resistance but would adjust. I finally got the AF confirmation beep when I autofocused on an object already in focus. Then I heard something pop from inside the camera (the mirror?) and the shutter finally tripped. The lens is working perfectly fine now. AF is accurate and the shutter trips consistently. MF adjustment is smoother too.

So what might have been going on here? My main concerns are: Does this indicate something problematic about the lens, and Did I potentially damage something by focusing/adjusting the lens in whatever paralyzed state it was in initially?

Thanks.

bvy,

I think the AF motor was stuck because the lens had been idle for along time. Turning the focus ring a little while set to AF would free it and it should then work as intended.

S

Had a similar thing with a mint 15-30mm EX, I think it had not been used for so long that although the autofocus motor worked the focus was way off. After a few goes it freed up and autofocuses accurately now. You probably have the same thing, the lens just has not been used for a few years.