Nikkor 500mm mirror lens question

[haris_ashraf]

Hi,

 

I have a Nikon 500mm mirror lens. I believe it is the latest model.

It has a rotating tripod collar but I cannot lock it. However, there

is a knob on the collar that does not turn or move up or down?

 

Is this knob supposed to turn and lock the tripod collar. i am

attaching a picture of the lens for reference.

 

Thanks for your replies.

 

Haris<div></div>

[Michael R Freeman]

<i>Is this knob supposed to turn and lock the tripod collar. </i><P>

Yes - something is amiss.

[tim_sewell]

Haris,

 

That knob is intended to screw in and out - screwed in, it does lock the tripod collar.

 

On my lens, the knob does not screw right out - it just slackens far enough to permit the tripod collar to rotate (but not far enough to lose the knob altogether!).

 

Others may be able to tell you how to fix your locking screw, but it might be a question of taking it to your nearest Nikon repair shop. I cannot imagine it could be a major job.

[alan_wilder1]

My guess is that the previous owner used too much force to unlock the collar by turning the knob too far counterclockwise. Try turning the knob clockwise with a bit more finger force. It should free up to be loose. Continue turning until snug which should lock the collar. If it won't budge send it of for minor repair to Nikon.

[haris_ashraf]

Thanks everyone. I will take it to Nikon Torrance facility for them to take a look.

 

Haris