dodgy focussing on a nikon lens (or camera?)

[bella]

hello kids,

i'm having a little trouble with my lens. it's a (this is what it says on it) af vr-nikkor 80-400mm, attached to a couple of year old nikon d7000.

the focussing has absolutely gone to poop the past few times i've tried to use it. i mean, it's trying but i don't think it's focussed perfectly anywhere on the photo. i've changed nothing, and done nothing differently since it actually worked, the light has been of the same quality. i've never used manual focus - the first time i took it out it threw itself across the car during an emergency brake procedure and that seems to have knocked something out. it used to focus fine - obviously not pro glass standards but now it just looks rubbish.

can anyone shed some light on whether it's the lens or the camera that might be at fault? any feedback very much appreciated before i take it to silverstone in september and it roundly shames my skillz. even more than i shame them myself

[Tim Falce]

Daft question but do you still have the focusing rectangle visible in the viewfinder and where you want it and is the switch on the side of the camera on AF or M? Does the lens have a motor in it? You could take it to a camera shop or Dixons and try another lens on it to check if it's the camera or lens, I'd suspect the body.

[bella]

not a daft question at all! it's all still focussing as normal, i tend to shift the autofocus point around depending on what shot i'm doing so i'm pretty aware of that, and the autofocus does shift around (i think it's on continuous). the switch is on af, iirc, but i'll check when i get home!

the only way i can describe it is that it's as if i'm using my 15 year old d70 again. it's as bad with stationary stuff as it is chasing things.

[Tim Falce]

Does the lens have a motor in it, if that's as new as the camera I'll assume it has.
Is the focusing laboured or does it sound OK albeit slow, and does it hunt backward and forward before finding something to focus on?
The only thing that springs to mind is maybe the focus drive has bent when it went flying but I can't see how. Have you tried it with a different lens on? are the images still OK, I.E. sharp?

[GORDON STREETER]

Bella PM sent.

[MikeHoyer]

Sounds like something has probably become dislodged in the lens - try it with another one to eliminate the camera, then attempt to bodge it yourself.

Only joking, take it to a repair shop!

[bella]

Originally Posted by Tim Falce

Does the lens have a motor in it, if that's as new as the camera I'll assume it has.
Is the focusing laboured or does it sound OK albeit slow, and does it hunt backward and forward before finding something to focus on?
The only thing that springs to mind is maybe the focus drive has bent when it went flying but I can't see how. Have you tried it with a different lens on? are the images still OK, I.E. sharp?

the lens is about 10 years old, but i think you're right, it has. the focussing isn't laboured, and it doesn't "hunt" for a focus lock any more than it normally does.

good point about trying it with another lens, i've got a shorter one for it that should produce similar results so i'll try that out at some point in the next few days.

it went flying about 6 years ago, so i'd be impressed if it's taken this long i don't recall knocking it or dropping it anywhere on either journey to either circuit the past few weekends, but i guess *something* must have happened for this to be the end result!