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Nikon Nikkor 180mm ED Focus Drift.

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11 replies to this topic

#1 RidleyRumpus

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Posted 19 September 2019 - 07:27 PM

I have just got myself one of the older Nikon 180mm lenses for my Nikon D5300

 

https://www.kenrockw...ikon/180f28.htm

 

But I am having some problems with the focus drifting, I think the weight of the lens makes the focus change slightly over time as the lens moves downwards.

 

Is there any way to stop this happening?



#2 SteveInNZ

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Posted 19 September 2019 - 08:03 PM

Gaffer tape.

 

I use it a lot.

 

Steve.



#3 Alen K

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Posted 19 September 2019 - 08:03 PM

Duct tape? I'm only half kidding.

 

(PS. Dang! Steve got there seconds ahead of me.)


Edited by Alen K, 19 September 2019 - 08:04 PM.


#4 kingjamez

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Posted 19 September 2019 - 08:12 PM

I use this lens for autoguiding. I use gaffers tape too. For imaging I use an autofocus gear that keeps the lens put.

-Jim

#5 dpaigen

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Posted 19 September 2019 - 08:32 PM

+1 for gaffers tape.  I keep a roll with my kit.


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#6 whwang

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Posted 19 September 2019 - 09:37 PM

This lens is famous for this.  I used a guider ring to hold the front end of the lens and put the ring and the camera on a dovetail plate.  This stabilizes the whole system, and prevents the focus shift.



#7 Steve OK

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Posted 20 September 2019 - 07:32 AM

This question came up here a couple of years ago, and I posted these pics of a possible solution:

 

post-31924-0-95948700-1483458635.jpg

 

post-31924-0-43920500-1483458670.jpg

 

This holds the focus well, and allows very fine focus adjustment.  

 

Steve



#8 kingjamez

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Posted 20 September 2019 - 08:20 AM

Good solution! I think I'll 3D print that.



#9 Steve OK

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Posted 20 September 2019 - 10:46 AM

It would be a good 3-D printer project!

 

I've also used a 1" or so piece of bicycle inner-tube, stretched around the barrel of a telephoto where the movable part meets the stationary part of the lens.  You can still rotate the barrel for focusing, but it stays in place once you find focus.  But it doesn't beat the fine focus allowed by the other contraption.

 

Steve



#10 Marco1968

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Posted 20 September 2019 - 02:46 PM

Greetings,

the double rings solution is also available commercially from TS:

https://www.teleskop...to-D-135mm.html

I use exactly this for my Nikon Ai-S 180 ED and works well.

All the Best,

Marco
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#11 JDShoots

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Posted 20 September 2019 - 07:32 PM

Like Steve's inner tube idea, I use a "Velcro Strap", that's what Amazon calls them.  It's for wrapping up a bundle of wires or something.   It has a small buckle on one end where I can wrap the velcro back on it's self and pull it tight.  Again, half is on the focus collar and half on the lens body.   The fuzzy parts of the velcro compress nicely and offers a lot of friction to hold the focusing collar.  


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#12 moxican

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Posted 21 September 2019 - 01:46 PM

I had it attached to a bit longer rail so I just put a rubber band hugging the lens and the rail. It always held focus after.




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