New-Nikkor 135/2!!!

[Gerhard2006]

On further analysis of your lens, I see that the focussing ring sactually sits up from the chrome ring  about 3/8" and it moves away from the chrome ring as it focusses. The Ais lens doesn't't do this, it stays with in 1/16" from the chrome ring the hole focussing distance. Hopefully this doesn't change  the disassembly to much? It's like yours has double helicoid like the 105 f4 macro? Just an observation  Gerry again 

[Roland Vink]

maybe this is a franken lens

It does have an interesting mix of early and late features:
- serial number belongs to K series
- AI style grip and AI max aperture post
- engraved LENS MADE IN JAPAN in white, found in K and very early AI lenses
- aperture coupling prong is from pressed sheet metal - usually found after engraving changed to MADE IN JAPAN in black

These AI lenses with early serial numbers often have a mix of features like this. I suspect Nikon kept some K serial numbers for spares, or never got round to using them before the AI series started, and decided to use them on production AI lenses at a later stage. I have seen this on a number of other lens models such as the 20/4 and 28-45/4.5.

[Gerhard2006]

 but the focus throw should be quite long

On my 135 Ais lens it's only 190 degrees from 1.3 to infinity. The Ai lenses were alway longer or rather more gradual.(finer thread)

[richardHaw]

It does have an interesting mix of early and late features:
- serial number belongs to K series
- AI style grip and AI max aperture post
- engraved LENS MADE IN JAPAN in white, found in K and very early AI lenses
- aperture coupling prong is from pressed sheet metal - usually found after engraving changed to MADE IN JAPAN in black

These AI lenses with early serial numbers often have a mix of features like this. I suspect Nikon kept some K serial numbers for spares, or never got round to using them before the AI series started, and decided to use them on production AI lenses at a later stage. I have seen this on a number of other lens models such as the 20/4 and 28-45/4.5.

must be a prototype 

[richardHaw]

but the focus throw should be quite long

On my 135 Ais lens it's only 190 degrees from 1.3 to infinity. The Ai lenses were alway longer or rather more gradual.(finer thread)

if it bothers you so much just send it to me lets see what i can do, Ai-S right?

[Frank Fremerey]

https://richardhaw.com/2019/07/21/repair-new-nikkor-135mm-f-2/

I love this lens a lot! 

chromatic aberration seems a bit high but it can be avoided, mostly.

in the 1980ies I was tempted to buy one of these used for my FM2n at the time. The seller offerd this and the 2.8/135 as well. The 2.8/135 was in excellent condition, sleek amd small, the 2/135 was extremly heavy, more than double the price and in medium good used condition. I was tempted but went for the 2.8 ... Happy hauling and shooting, Richard!

[Roland Vink]

I checked the records in my database - lenses in the "New Nikkor" (K) series have serial numbers 175011up to a recorded high of 179779, for a total of at least 4769 units. Most that I have seen after 178xxx are actually AI, so a significant proportion are not actually the K version. The original K version would be quite rare.

For more reading on this lens, this is very interesting: https://imaging.nikon.com/history/story/0030/index.htm

[richardHaw]

I checked the records in my database - lenses in the "New Nikkor" (K) series have serial numbers 175011up to a recorded high of 179779, for a total of at least 4769 units. Most that I have seen after 178xxx are actually AI, so a significant proportion are not actually the K version. The original K version would be quite rare.

For more reading on this lens, this is very interesting: https://imaging.nikon.com/history/story/0030/index.htm

So this is actually an Ai? i am now confused 

[richardHaw]

in the 1980ies I was tempted to buy one of these used for my FM2n at the time. The seller offerd this and the 2.8/135 as well. The 2.8/135 was in excellent condition, sleek amd small, the 2/135 was extremly heavy, more than double the price and in medium good used condition. I was tempted but went for the 2.8 ... Happy hauling and shooting, Richard!

it's the best in terms of cost/performance. 

[Roland Vink]

So this is actually an Ai? i am now confused 

As you know, the AI series officially starts at 190001, the original New Nikkors have serial numbers from 175011 - 179779. These versions are almost identical optically and mechanically, apart from a few minor changes for the AI version:
- AI aperture ring
- Different rear lens protector, AI version has max aperture indexing post
- New Nikkor rubber focus grip is glossy black, AI is dark grey matte and less finely knurled
There might be some internal changes or improvements along the way but that's about it.

It turns out that many lenses with New Nikkor serial numbers are actually AI - they  were built as AI and are not AI converted. I have seen this with many lens models including the 20/4, 35/1.4, 135/2 and 28-45/4.5. I guess Nikon had left over parts with K serial numbers that they decided to use up after AI production started. So yes, your lens is actually AI

[richardHaw]

As you know, the AI series officially starts at 190001, the original New Nikkors have serial numbers from 175011 - 179779. These versions are almost identical optically and mechanically, apart from a few minor changes for the AI version:
- AI aperture ring
- Different rear lens protector, AI version has max aperture indexing post
- New Nikkor rubber focus grip is glossy black, AI is dark grey matte and less finely knurled
There might be some internal changes or improvements along the way but that's about it.

It turns out that many lenses with New Nikkor serial numbers are actually AI - they  were built as AI and are not AI converted. I have seen this with many lens models including the 20/4, 35/1.4, 135/2 and 28-45/4.5. I guess Nikon had left over parts with K serial numbers that they decided to use up after AI production started. So yes, your lens is actually AI

thanks, so this is actually an Ai in disguise