In article , javd@sirius.com says...
>In article ,
>Rudy Garcia wrote:

>>Hmm, I was under the impresion that from AI to AI-S, the change was to add
>>a milled recess on the rear mount surface. The depth of the recess was
>>sensed by a spring loaded pin in the camera and is used to determine the
>>focal length range of the lens.

No - see D. Jacobson's post...

>I know at one point Nikon offered this simple 'S' conversion for $17.50,
>do not know if they still do.

No, it was an exchange of an AI aperture ring for the non-AI ring - and
unfortunately they do not still do it. A few private "AI'ers" still cut
the necessary notch in the aperture ring for about $30 each.
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