Help please: AI or NON AI

[Asha]

OK I need someone who can without any doubt confirm wether this is an AI or NON AI lens.

 

[gramps]

Certainly looks like an AI Asha

(http://www.kenrockwell.com/nikon/images1/50mm-f2/ai/D3S_2769-1200.jpg)

 

[Ceejay]

Definitely AI, you can tell by the ridge on rear of the lens.

C

 

[freecom2]

AI. 2 rows of aperture numbers, serial number, coupling ridge, lowest f/stop is not orange (that would be AI-S), holes in the rabbit ears.

 

[Asha]

I was drawn to think AI too until I read this

Quote (2nd Paragraph)

"The most distinctive characteristics of the Non-AI lenses are the metering prong without “nostrils” (2 smaller holes on either side of the opening) and the plain stainless steel base with 5 mounting screws."


Totally confused as the prong on the lens I've posted does have "nostrils which would suggest AI but the base plate has 5 mounting screws which suggests NON AI

 

[Asha]

Will be cool if it is AI then as would work on my F/60 / D50 / D80 (albiet with mf and no metering) as well as perfectly on my FE

 

[TheGreatSoprendo]

OK, here's why you're confused:

This is a lens that started life pre-AI. Often known as K series, in that it has the same general cosmetic design as the later lenses, it is very different looking to previous pre-AI lenses which didn't have the rubber grip around the focusing ring, for instance, and had a metal scalloped variety instead.

Its serial number puts it smack in the middle of this group of lenses. See here:

http://www.photosynthesis.co.nz/nikon/lenses.html#50slow

Subsequently, it has received the official Nikon conversion to AI, using a new AI aperture ring.

So it is indeed an AI lens, or strictly speaking an AI-converted lens. However in every practical sense it is exactly the same as the slightly later AI version.

So feel free to use on your newer bodies.

It is also a beauty (I have one myself) - a fantastic performer (at least on film, anyway).

 

[Asha]

Definitely AI, you can tell by the ridge on rear of the lens.

C

AI. 2 rows of aperture numbers, serial number, coupling ridge, lowest f/stop is not orange (that would be AI-S), holes in the rabbit ears.

OK, here's why you're confused:

This is a lens that started life pre-AI. Often known as K series, in that it has the same general cosmetic design as the later lenses, it is very different looking to previous pre-AI lenses which didn't have the rubber grip around the focusing ring, for instance, and had a metal scalloped variety instead.

Its serial number puts it smack in the middle of this group of lenses. See here:

http://www.photosynthesis.co.nz/nikon/lenses.html#50slow

Subsequently, it has received the official Nikon conversion to AI, using a new AI aperture ring.

So it is indeed an AI lens, or strictly speaking an AI-converted lens. However in every practical sense it is exactly the same as the slightly later AI version.

So feel free to use on your newer bodies.

It is also a beauty (I have one myself) - a fantastic performer (at least on film, anyway).

Thank you ever so much for the clarification guys.....Naturally the last thing I wanted to was try it on a digi body and s**** the lens and/or camera body.

Just tried it on the D50 :

Cool or what

 

[Steve Smith]

Naturally the last thing I wanted to was try it on a digi body and s**** the lens and/or camera body.

It would still fit if it was pre AI wouldn't it?

EDIT: I have just put a pre AI lens onto my old Nikon D100 and it seems o.k. (although the camera was broken already!). So yes.


Steve.

 

[Morinaka]

Non/Pre-AI will mount but it don't meter like an AI lens will. Easiest way to tell an AI from Non-AI is that AI/AI'd/AI-s/AF/AF-D lenses all have two rows of aperture numbers on the lens.

 

[Steve Smith]

Compatibility charts on Nikon's website (this one for D3200).

http://imaging.nikon.com/lineup/dslr/d3200/compatibility02.htm


Steve.

 

[Asha]

It would still fit if it was pre AI wouldn't it?

EDIT: I have just put a pre AI lens onto my old Nikon D100 and it seems o.k. (although the camera was broken already!). So yes.


Steve.

Non/Pre-AI will mount but it don't meter like an AI lens will. Easiest way to tell an AI from Non-AI is that AI/AI'd/AI-s/AF/AF-D lenses all have two rows of aperture numbers on the lens.

According to this info it is a no no to use Pre AI lenses on certain bodies....hence my hesitation in trying the lens on my other nikon bodies.:

 

[kenm]

Well for sure you can't put a non-AI lens on an FM2n, for example, so don't try it on one of those. Your modified one should be fine though.

 

[Steve Smith]

I have found lots of articles that state that you can't put a pre AI lens on a new camera but I haven't found one which tells me why.

My mechanical engineering mind wants to know why!

Looking at pre AI, AI, series E and AF-S lenses here, I really can't see what the problem might be but there must be one otherwise there wouldn't be so many people saying don't do it.

(unless it's similar to the paranoia about using old flashes on DSLRs!!).


Steve.

 

[Asha]

I have found lots of articles that state that you can't put a pre AI lens on a new camera but I haven't found one which tells me why.

My mechanical engineering mind wants to know why!

Looking at pre AI, AI, series E and AF-S lenses here, I really can't see what the problem might be but there must be one otherwise there wouldn't be so many people saying don't do it.

(unless it's similar to the paranoia about using old flashes on DSLRs!!).


Steve.

I don't know for sure tbh but I would hazard a guess to believe there may be a collision between mirror and rear element of lens thus causing damage.....From what I understand this was more of a problem with Canon than with Nikon.

No doubt one of the old croners will crawl out the woodwork with a thorough response to settle the most mechanically engineered minds.

 

[kenm]

In the case of the FM2n, it won't fit, and forcing it will break something. It says so in the camera manual and having very gently tried it I am inclined to accept that. Don't know about other cameras, but Asha's link looks about right.

 

[Asha]

Seeing as we're on lens compatability, I have a couple of third party lenses ( Sigma) which are Nikon fit.....regardless of vignetting, metering and focusing....would these work on, for example, the FE or F60 without causing damage?

 

[retrogamer1990]

Seeing as we're on lens compatability, I have a couple of third party lenses ( Sigma) which are Nikon fit.....regardless of vignetting, metering and focusing....would these work on, for example, the FE or F60 without causing damage?

If they're AI, yes.

 

[retrogamer1990]

I have found lots of articles that state that you can't put a pre AI lens on a new camera but I haven't found one which tells me why.

My mechanical engineering mind wants to know why!

Looking at pre AI, AI, series E and AF-S lenses here, I really can't see what the problem might be but there must be one otherwise there wouldn't be so many people saying don't do it.

(unless it's similar to the paranoia about using old flashes on DSLRs!!).


Steve.

I've found that they don't fit it's because the depth of the very back part of the lens (where the aperture index 'ridge' is on AI lenses) is slightly greater with non-ai lenses which causes a very tight fit - so you can't move the aperture ring - or not at all. Grinding this down and cutting the correct ridge out is basically how you DIY convert a lens to AI

I think!


edit: also, you can totally use non-ai lenses on the D40/x

 

[Asha]

If they're AI, yes.

Thanks but they are later than that....one is a an 18-200 DC like this

the other is a 170-500 APO DG like this

It's unlikely i would use them on the FE tbh but might be tempted to try the 170-500 on the F60 next month when the carnaval comes to town (assuming it will work of course!) ...make a change to capture the event on colour film instead of on digital like I've done in previous years

 

[retrogamer1990]

Thanks but they are later than that....one is a an 18-200 DC like this

the other is a 170-500 APO DG like this

It's unlikely i would use them on the FE tbh but might be tempted to try the 170-500 on the F60 next month when the carnaval comes to town (assuming it will work of course!) ...make a change to capture the event on colour film instead of on digital like I've done in previous years

If there's no aperture ring, you can't use them on manual film cameras

edit: well... you CAN if you want to shoot at f/32 or hack the iris open

all systems go on the F60 though!

 

[Morinaka]

I have a Nikon FE and in the FE manual it says when using Non-AI lenses that you have to "retract" the AI coupling prong, which you can do on an FE but not on any other Nikon camera with an AI prong, that i know of anyway. Which would suggest that the lower end DSLR Nikon without AI prongs would mount Non-AI lenses easier?

 

[Asha]

If there's no aperture ring, you can't use them on manual film cameras

edit: well... you CAN if you want to shoot at f/32 or hack the iris open

all systems go on the F60 though!

Good news re the F60 then .....Instead of two digi set ups on my shoulders, I reckon it will be the F60 with the tele and the FE with the 50mm

 

[TheBigYin]

I think the sigma DC lenses stand for digital-crippled - i.e. they're set up for the smaller (aps-c ??) digital sensor, rather than full frame 35mm - so it may connect and do it's stuff, but the image circle will be such that it'll look like you've shot down a tube of pringles (well - thats what the sigma 10-20DC looked like through the viewfinder of the EOS3)

 

[Steve Smith]

I've found that they don't fit it's because the depth of the very back part of the lens (where the aperture index 'ridge' is on AI lenses) is slightly greater with non-ai lenses which causes a very tight fit - so you can't move the aperture ring - or not at all. Grinding this down and cutting the correct ridge out is basically how you DIY convert a lens to AI

Most DIY AI conversions just file out a slot in the existing ring. I suppose what they mean then is an AI converted lens must be properly converted with a new aperture ring which is flush with the mating face of the lens mount rather than overhanging like the pre AI types.

Just taking out a small area for the coupling wouldn't be enough.

And I have no intention of machining down the aperture rings of my pre AI lenses!


Steve.

 

[retrogamer1990]

I think the sigma DC lenses stand for digital-crippled - i.e. they're set up for the smaller (aps-c ??) digital sensor, rather than full frame 35mm - so it may connect and do it's stuff, but the image circle will be such that it'll look like you've shot down a tube of pringles (well - thats what the sigma 10-20DC looked like through the viewfinder of the EOS3)

ah maybe, I'm not so familiar with the third party stuff

 

[freecom2]

To the best of my knowledge:

Basically, a pre-AI lens has a solid piece of metal at the lens mount side - on an AI/AI-S/AF/AF-D lens, this line of metal is partly filed away to interact with the AI coupling mechanism. This is a small stub around the Nikon F lens mount that should be visible on most film Nikons, and most prosumer digital Nikons.

Mounting a pre-AI lens on a camera that is built for AI and later means that the metal will strike and potentially damage this AI coupling mechanism.

This is the reason why you can usually mount pre-AI lenses on entry level Nikons - the very ones that do not have compatibility with the older lenses, because they have no means of gauging aperture via the AI coupling mechanism.

 

[TheGreatSoprendo]

I have a Nikon FE and in the FE manual it says when using Non-AI lenses that you have to "retract" the AI coupling prong, which you can do on an FE but not on any other Nikon camera with an AI prong, that i know of anyway. Which would suggest that the lower end DSLR Nikon without AI prongs would mount Non-AI lenses easier?

Slight correction of detail: the tab can also be flipped on a few others in exactly the same way: Nikkormat FT3, EL2, FM, F3, F4 off the top of my head. Also on the later AI version F2 models (F2A, F2AS) there is a similar function. How geeky am I....

 

[trevorbray]

Slight correction of detail: the tab can also be flipped on a few others in exactly the same way: Nikkormat FT3, EL2, FM, F3, F4 off the top of my head. Also on the later AI version F2 models (F2A, F2AS) there is a similar function. How geeky am I....

Hey...Nikon geeks can do no wrong in my book...

 

[freecom2]

Importantly, this function doesn't necessarily follow form - for instance, you can do it on the FE/FM but not the FE2/FM2/FM3A.

 

[Steve Smith]

Mounting a pre-AI lens on a camera that is built for AI and later means that the metal will strike and potentially damage this AI coupling mechanism.

This is the reason why you can usually mount pre-AI lenses on entry level Nikons

As far as I am aware, the D3200 does not have the AI tab on the body and I know my D100 doesn't (unless it was hiding from me) yet I see advice saying not to mount pre AI lenses on a D3200.

As you imply, if these cameras did have the tab, they could meter AI lenses.


Steve.

 

[freecom2]

Apologies Steve, I assumed (wrongly) that the early Nikon digital bodies would be as compatible with older film era lenses as possible - assuming that the D1 and D100 would both have tabs (I believe the D1 does, not your D100 indeed).

 

[Steve Smith]

There is a D3100/D3200 group on Flickr. I found this today:

Today I went to the service centre and get back my Nikon D3100, there was a small damage in a major part they have replaced it, I also bring my OLD PRE AI LENS to let them see if it can cause any problem ........they checked and said its fine to use that lens in D3100 body....I am really quite happy for that.........

Me too!


On the same thread:

if you look at my stream, my most recent 12 shots are from a 105 f/2.5 pre ai. I bought it off a guy on ebay for around 60 bucks.

That's the lens I want to try.


Have a look at the table about a third of the way down this page: http://www.bythom.com/lensacronyms.htm

assuming that the D1 and D100 would both have tabs (I believe the D1 does, not your D100 indeed).

It fits fine on the D100. If it wasn't broken I could tell you if it works. However, the table in the page I linked to above says do not mount on a D100!


One more quote from that Flickr group:

Since the D3100 and a lot of other entry-level cameras don't meter with non-CPU lenses this aperture coupling isn't there. That's why you can use non-AI lenses with no problem.

That's what I originally thought. If there is no AI tab on the camera then the lens doesn't have to be AI to mount. Doesn't explain the D100 exception though.


Steve.

 

[Nod]

Thanks but they are later than that....one is a an 18-200 DC like this

the other is a 170-500 APO DG like this

It's unlikely i would use them on the FE tbh but might be tempted to try the 170-500 on the F60 next month when the carnaval comes to town (assuming it will work of course!) ...make a change to capture the event on colour film instead of on digital like I've done in previous years

I think the sigma DC lenses stand for digital-crippled - i.e. they're set up for the smaller (aps-c ??) digital sensor, rather than full frame 35mm - so it may connect and do it's stuff, but the image circle will be such that it'll look like you've shot down a tube of pringles (well - thats what the sigma 10-20DC looked like through the viewfinder of the EOS3)

I can confirm that the 170-500 will work just fine on the F60 (well, mine did on my F65!), although of the long Sigma zooms, it's possibly the least good. Big, heavy b****r to lug about on the off chance too. IIRC, they have an aperture ring so can be used on legacy bodies (or at least most legacy bodies) as well.

The 18-200 will also fit and work on an AF body but will (as TBY suggests) vignette horribly on 35mm (and FF D*g*t*l!). As I'm sure you know, DC is Sigma's equivalent to Nikon's Dx and DG is analagous to Nikon's Fx.

IIRC, "D" series Nikkors have the aperture ring while "G" series are completely electronically controlled. Not sure if the Canon trick of detatching the lens from a body capable of controlling a G lens while the DoF preview button is held in works with G series (or similar) lenses and don't want to risk it!

 

[Steve Smith]

In the spirit of one of my favourite old sayings 'those who say something cannot be done shouldn't interrupt those actually doing it' I tried my pre AI lenses on my D3200 and can confirm that they work fine.

I am quite pleased that I can use my f2.5 105mm lens on it as that's one of the reasons I bought the camera!


Steve.