Did Tamron 18-270 PZD fix auto focus problems?

[SuzieQ]

Hi Photographers!

I have a Nikon D40 and I used to have a Tamron 18-270 which I absolutely loved except that I had problems with the autofocus. It wouldn't "lock on" unless the conditions were perfect and so I almost always had to switch to manual mode and by then I usually lost the shot. So, I sold the Tamron. Now Tamron has a new lens that is exactly the same except that it has PZD (Piezo Drive) ultrasonic autofocus motor. Does anyone know if PZD fixed the autofocus problems? Please let me know! I'm a bit worried about buying Tamron again after the problems I had with the autofocus on the last one and so I'm considering Sigma's 18-250 as an alternative.

Please advise if you have any knowledge or info on this subject.

Thank-you.

 

[KmH]

Probably not, because the focus motor has more to do with how fast a lens focuses, not as much with how accurately the lens focuses.

The sensor that detects focus is in the bottom of your D40, not the lens. The lens just provides the light the D40 Multi-CAM 230 auto focus module uses. Of course, your D40 only has the 3 focus points, and none of them are the more accurate cross-type focus points found in the more expensive and newer Nikon's that use the Multi-CAM 1000, 3500DX, 3500FX, and the newest Multi-CAM 4800DX auto focus module found in the D7000.

Autofocus - Wikipedia, the free encyclopedia

By the way. There is a secondary mirror, and a window between the lens and the auto focus module in your D40. Are both clean?