Pre AI 500mm f/8 cat lens: Does it need conversion?

[jeff_emtman]

I shoot with a d80 (in addition to my FT2). I'm buying the old 500mm f/8 cat lens

from someone. I was prepared to either pay for the AI modification to be made, or

to do it myself so that I could use the lens on my digicam.

 

However, if my memory serves me, the conflict with pre AI lenses has to do with

the aperture prong. When I was trying it out today, I noticed that the lens is a

fixed f/8 and thus has no aperture ring/prong. Do I need to convert this lens before

using it on a d80, or not?

 

Thanks,

~Jeff

[juanjo_viagran]

that lens doesn't have aperture ring.. is fixed f:8 and doesn't need conversion to use with a D80 or ANY other Nikon DSLR.

[tri-x1]

I'm not the final word but it would see that if the lens doesn't have an aperture ring there's nothing to convert.

[patrick_mcintyre1]

I'm not sure that the aperture ring itself is the problem. My pre-AI Nikkor lenses have a lip around the edge that hangs over the the mount and interferes with the AI indexing lever. My AF-S lenses and a (what appears to be a non-AI) Vivitar 135mm have a flush edge on the mount which clears the lever. I had to remove the indexing tab from a teleconverter to get those pre-AI lenses to mount to it.

 

Mounted on my D40, the AF-S lenses and the Vivitar have a visible gap all the way around the lens between the back of the lens and the body through which the chrome body mount is visible - the pre-AI Nikkors fit flush against the body with no gap.

 

Look and see if the lens has a raised lip or not - if not, it should work without modification.

[joe_a2]

Jeff....The pre-AI 500mm cat will not fit on your D80 unless it has been updated to AI. The problem is the lip, as Patrick described.

[douglas_greenberg]

I purchased a pre-AI 1000mm. f11 cat a few years ago. It required no conversion at all. I wonder if the 500mm. is the same.

[scott_warn]

A WARNING. At about the sevenn o'clock position relative to the lens mount with the camera facing you there is a small lever. This is the minimum aperture signal lever. With some of these lenses, there is an interference between the rear surface of the lens and this lever. Basically, mounting the lens will cause it to try and push that lever STRAIGHT INTO THE CAMERA BODY. THAT WILL BREAK THIS LEVER. So, with these early lens you have to watch that lever VERY CLOSELY the first time that you try and mount the lens and, if you see any contact between the lens and that lever, STOP and don't try using that lens on your D80.

 

Unfortunately, if you do find that this lens won't clear the minimum aperture signal lever, you may find that modifying the lens to fit your D80 to be expensive. Bascially, you'll have to find a machine shop who would be willing to machine the rear surface of the lens until it just barely clears that lever. Which will have to be done by trial and error because if too much material is removed you may break into the interior of the lens.

[nickc1]

This link may help

 

http://www.aiconversions.com/

[douglas_greenberg]

Yes, if you email John White he will be happy to provide you with an answer. When it comes to AI conversion issues, "he's the man."

[jeff_emtman]

Thanks Douglas and others. I sent mr. White an email, hopefully he will reply soon.

 

~Jeff

[jeff_emtman]

Update: I received an email back from John White. He says that the lens can be mounted without conversion.

 

thanks everyone.

~Jeff

[scott_murphy_photography]

<p>Mine works perfectly on my D-700 and the focus confirmation comes in very handy, though I replaced the D700 screen with a microprism one<br>

<br />"<a href="../photodb/user?user_id=540188">Douglas Greenberg</a> <a href="../member-status-icons"><img title="Subscriber" src="http://static.photo.net/v3graphics/member-status-icons/sub7.gif" alt="" /></a>, Jun 07, 2008; 09:24 a.m.<br />I purchased a "pre-AI" 1000mm. f11 cat a few years ago. It required no conversion at all. I wonder if the 500mm. is the same"<br>

<br />Doug, there is no such thing as an AI mirror lens. They all have fixed apertures so there is no aperture ring to do any indexing</p>