D90 Auto Focus Problem

I am new to Nikon and DSLR photography and had my newly acquired D90 with 18mm - 105mm lens out at the weekend. All was going fine for the first hour at a UK Jubilee street party when the lens stopped auto-focussing properly and starting hunting. The lens seemed unable to focus on any object, focussing back and fourth. Switching to MF was fine, going back to AF, problem re-occurred. Removed and refitted lens, cleaned contacts (though as a new camera they wern't dirty) - problem remained. Removed UV filter and problem went away. Good light all through this experience. Any ideas before I take camera back to shop?

Mike

Hi Mike and welcome...You say you removed the filter and the problem went away...If this is so I don't think the camera is the problem...With the lens hunting I would say the light was insufficient for the settings...

What mode were you shooting in...Did you clean the lens contact points...

You may have a UV filter designed for a film camera and not a digital. When I purchased my D90 I also bought a 70-300VR lens with it. They gave me a UV filter free and I never was able to take a decent shot using this lens. I finally took off the UV filter and it was sharp as a tack and I was very happy with the lens. What I found out was that they had given me a non digital UV filter that just would not work right. After I changed it to a digital UV the pictures were still very sharp and I was finally happy with my lens, Jeff

Thanks for the replies guys. I was shooting in both Auto and Auto (-flash mode). I have since tried to recreate the problem and in both modes I cannot get it to happen again both with UV filter on and off. Today it's raining in the UK so light is poor but camera working fine. Very curious. I shall have to wait and see if it happens again and try and be a bit clearer on the settings I am using and if all lese fails take the camera back. Mike