Zoom ring stuck

I have a Nikon d50 and 2 Sigma lenses, a 10-20mm and a 18-200mm. Both were workin fine this morning. After changing lense a couple of times, I found that the zoom ring on each lens was set at the widest angle and the zoom rings would not function. I do not see anything relevant in the minimal instructions that came with the lenses. Any suggestions would be appreciated.

djk1385

Do the zoom rings work when the lenses are off the camera?

If so, then there's a problem when they are locked into position. You could try removing and carefully reseating the lenses.

Also to look for are any locking rings or switches on the lenses, which are usually intended to stop the lenses from becoming fully extended when being carried.

Hope you find the answer!

John