Nikkor 2.8/28mm AIS question

[richard_laepple]

Hello all. I have a question to owners of a 2.8/28mm AIS Nikkor. I

got a fine one from eBay today, looks really great. After turning the

focus ring to near distances two little holes appear on the lens

barrel. I was surprised seeing no screws. One hole shows something, i

don't know what, could be a screw... Is this ok? I can't see any

thread. The holes were a bit oily, everything seems to work smooth,

turning the focus ring feels very good. Perhaps you can take a look

on your lens? Thanks a lot.<div></div>

[Jerry_]

If it were my 'purchase,' I would do my best to return the lens. Someone has worked on the lens and (maybe) didn't notice a screw or two were surplus things on the table.

[alan_olander1664878205]

I looked at my 28mm/2.8 and there are two holes about 180 degree apart with screws in both of them. One is set a little deeper than the other, but there is definitely a screw there. The screw in your lens may just have fallen out, but they're usually "locked" in pretty well.

[jeff h.]

I don't have that exact lens, but on a few of my lenses those missing screws are little set screws that hold the front element in place.

[david_h._hartman]

"I was surprised seeing no screws. One hole shows

something, i don't know what, could be a screw... Is this ok? I

can't see any thread." --Richard Laepple<br>

<br>

Its a cost cutting measure. In the old days there would

have been a set screw. There is a drop of thread lock there that

may look oily. Its a real thrill the first time you put a

jewelers screw driver in and the blade climbs the thread and

feels for all the world like the head of the screw is shot. This

is common on AIS Nikkors. My 28/2.0 AIS Nikkor has this thought

the hole is under the rubber focus grip.<br>

<br>

The lens is fine unless you can accutally identify this stuff as

oil which is doubtful. There is no need to return the lens.<br>

<br>

Best,<br>

<br>

Dave Hartman.

[david_h._hartman]

For those who do their own lens repair you soften the thread

lock with acetone applied with a small pair of precision tweezers.

Capillary action holds a very tiny quantity of solvent. You apply

it several times over a period of maybe 3 to 5 minutes. Most of

the lenses Ive repaired have a set screw. <br>

<br>

Im not a professional camera repairman. When I first

encountered this I made a very worried phone call to a camera

repairman friend who explained whats up. Even if there were

a set screw there is often some of the thread lock at the hole that can look like oil thats oozed out. <br>

<br>

The scenario for applying acetone is the way Ive seen my

camera repairman friend apply acetone to the screws on the rear

bayonet of manual focus Nikkors. These are locked with a thread

lock that looks similar to white, hight temp Locktite.<br>

<br>

Im not recommending self lens repair, YMMV!<br>

<br>

DHH

[richard_laepple]

Thanks so far. But what are these little holes/screws for? What happens when the screws are missing? Ok, I'll get oily hands, perhaps...

[david_h._hartman]

If the hole is supposed to have a set screw and doesnt

that ring, the filter ring, will unscrew fairly easily. If it has

no set screw but rather a drop of something similar to Red

Loctite you might damage something before it will give. I dont

know and I wouldnt try. If the filter ring is tight the

lens is fine.<br>

<br>

Under the filter ring there is a brass locking ring with four

screws that secure the focus ring to part of the helical focus

device. That brass locking ring is used to collimate the lens (adjust

its infinity focus). You would also notice that on this lens, the

28/2.8 AIS, and any of the 28/2.0 Nikkors that these have CRC or

close range correction that acts on the front of the lens.<br>

<br>

If you turn the focus ring very carefully you may feel a little

play and hear a faint click. This is normal. There is a follower

in a slot and what youd feel is the play in it. Im

not completely sure but I think the first 3 elements in 3 groups

(both lenses) are in their own barrel and I they are ridding on

there own sub-helical. Anyway some of the elements at the front

of the lens move at a different rate than the rest of the lens as

you focus closer and this creates the close range correction.<br>

<br>

If you like you can loupe the sides of the hole shown in your

photo. You will most like see no threads for a set screw. Looking

straight into the hold you will see the threads for the filter

ring below. Even if the hole has threads in the sides if there is

a thread lock in it then its OK. There won't be any oil.

The threads for the filter ring are dry.<br>

<br>

I hope this makes sense. Im dog tired and the brain is

shutting down. Im off for a shower and then all the bed.<br>

<br>

Regards,<br>

<br>

Dave.

[richard_laepple]

Dave, thanks for spending your time. Hope you slept well. I have never seperated a lens in my life and I am not hot to do this. So, what is the best to do? I've contacted the seller, no answer so far. There are two thoughts spinning around in my head: 1. I don't want a lens missing some parts. Who on earth knows what other people did with it. 2. This lens looks pretty good, has almost no using marks. Glass is in perfect condition. Even no sign of use at the lens mount. BTW I can hear nothing, no CRC-klick (I heard it on other lenses before and do know what you mean), there is no play at all. -- I hate eBay!!!

[richard_laepple]

In the meantime the seller sent me a pic of another 28 lens he checked at the photo shop. It has the same hole. The conclusion: this is normal.

[david_h._hartman]

<em>"1. I don't want a lens missing some parts. Who on

earth knows what other people did with it." --Richard

Laepple<br>

</em><br>

Since this is an AIS its probably not missing anything it

had the day it left the factory. I would not worry. I have two 28/2.0

AIS Nikkors and they have no set screws in small holes like yours.

The Loctite does the job of a set screw very well.<br>

<br>

<em>2. This lens looks pretty good, has almost no using marks.

Glass is in perfect condition. Even no sign of use at the lens

mount.<br>

</em><br>

It looks like some kind person bought this lens and stored it

carefully just so you could buy it at a reduced price. Take it

out and use it, enjoy it!. Its one of Nikons finest.<br>

<br>

Im amazed to buy equipment that shows no signs of use.

About a year ago I bought a Nikon F3 with only three superficial

scratches on the base plate. There was no sign that film had ever

been in the camera. I was a little concerned about lack of use at

first.<br>

<br>

I bought two lenses, 135/2.8 AIS and 28/2.0 AIS about 6 months

ago complete with boxes and instructions, no sign of use. These

came for KEH.com. I saved more than $200.00 (USD) compared to

B&H gray.<br>

<br>

Best,<br>

<br>

Dave Hartman. <br>

<br>

Postscript: this is the only 28/2.8 AIS to own (in my opinion).

It shares a spot in Bjorn Rorsletts "Best of the Best"

with the 28/2.0. Id like a 28/2.8 AIS as its noted to

be extremely sharp close up and it focus down to just 0.2m.<br>

<br>

<a href="http://www.naturfotograf.com/bestof.html" target="_new"><u>http://www.naturfotograf.com/bestof.html</u></a><br>

<br>

<a href="http://www.naturfotograf.com/lens_surv.html"

target="_new"><u>http://www.naturfotograf.com/lens_surv.html</u></a><br>

<br>

<a href="http://www.naturfotograf.com" target="_new"><u>http://www.naturfotograf.com</u></a><br>

[david_h._hartman]

Oops! I ment to say it's the only 28/2.8 Nikkor to own. None of the others have CRC.

[richard_laepple]

Dave, I know the various reviews of this lens, also Ken Rockwell's. 28mm was so far not "my" focal length, I mostly use 50 upwards, 85 is my favourite length (have a nice 1,8/85, latest version, AI'd, 1,4/85 is too expensive). Since prices of these lenses drop more and more down I decided to try a 2.8/28 and 2/35 again. The close up distance of the 28 was my main reason to buy the AIS and not the older AI. I share your love for unused equipment. But it's hard to find, and many people (at ebay e.g.) talk their gear nicer as it is. Even professional sellers are sometimes not as reliable as it should be. But, to come back to my 28, I will keep and try it with my F3 and FM.