Are 85mm 1.4 IF lenses supposed to be a bit shaky inside?

<p>Hi, I have just bought a second hand 'as new' nikon 85mm F1.4 lens. It seems to focus ok both manual and automatic. <br>

When you move it it sometime makes a quiet clunk like there is something moving inside.<br>

Is this normal? <br>

I cant find another of the same lenses in the city I live in. So I would appreciate it if someone wouldn't mind checking their lens for me. I am considering returning the lens. <br>

Many thanks<br>

Dani</p>

<p>No. Of the 6 lenses I own it is by far the most solid. Just out of curiosity what type of body are you using it with?</p>

<p>This was addressed in another forum recently (dpreview.com I think) and the consensus was that screw drive lenses can have varying amounts of "clunk" when lightly shaken back and forth.<br>

My 85mm has this sound. I bought it brand new and it works flawlessly. I wouldn't worry about it. My 80-200mm has a clunk sound and was also bought new and works flawlessly. I think it is just a bit of "slop" internally so that the lens will autofocus quickly without binding.</p>

<p>Mine is definitely pretty solid.</p>

<p>Thanks, for the information. It seems some of you have lenses which are a bit shaky inside and others do not. It does not seem to effect the images. I think I will go looking for one that is not shaky. Its a shame becuase it is such a nice lens. I think the shakyness is inside, the lens in the internal focusing, so its hard to see where it is happening. <br>

thanks again<br>

Dani</p>

<p>"....I think it is just a bit of "slop" internally... "<br>

That would actually worry me because it might not focus the lens very precisely in situations where the distance to subject and therefore the focus point changes back and forth. This is easy to overlook as one might attribute it to user error.</p>

<p>It is a bit tricky to test but the way to do this is to do a focus test say on a 45 degree tilted object and repeatedly get into focus from behind and from the front. If there is slack it would show in a set of images as both front and back-focus. As a control one can fix the lens say by tape and change the focal plane by slightly moving back and forth.</p>