[spas13]

I have a non-AI 200 mm Q tele lens made in the 60's. I want to use it on my D40 but I saw an article which reads : non-AI lenses manufactured prior to 1977 can cause mechanical damage to later model bodies unless they are modified to the AI specification.

I am worrying whether this 200 mm lens will cause any damage to my D40 body if I mount it? Grateful for any advice. Thanks

[barryspc]

I am not sure about the 200mm but I tried mounting a non-AI 135mm f2 on my D70 and it works fine

[spas13]

Dear Barryspc,

If it can be mounted on a D70, can I assume that it can also be safely mounted on my D40 without any potential danger? Thanks in advance for your further advice.

[老叟]

don't expect to much,ais is much better

[barryspc]

I have to say my 135 f2 is a much newer lens than your Q lens. and I have never seen the Q lens

extract from kenrockwell.com

"Lens Compatibility

My D40 only autofocuses with the latest AF-S lenses, and also the the older, professional, AF-I lenses.

You'll have to focus manually with traditional AF lenses, which means forget about older lenses except macros (I always focus those manually) and fisheyes and ultrawides (easy to focus).

Every AF lens made in the past 20 years meters and exposes perfectly; it's just the autofocus which won't work.

Every manual focus lens made since 1959 also works fine, if you don't mind focusing by hand and guessing at the exposure.

This is a smaller deal than it sounds, since the included kit lens and other modern lenses obsolete the older lenses I thought I might be using with this.

This is why I never waste my money on off-brands. All the Nikon lenses I've been buying since the late 1990s, like my 24-85mm AF-S, 80-200mm AF-S and ten-year-old 400mm f/2.8 AF-I work perfectly."

[spas13]

Dear barry,

Thanks for your advice. I don't mind focusing manually and doing guesswork. Afterall, I can try using the telephoto 200 mm Q lens to take several shots with different apertures and choose the one I consider satisfactory. I just cannot figure out why the article I read warns that there would mechanical damage to my D40 body if I mount the non-AI lens, save it has been modified to AI specification.

[spas13]

Dear C-hings,

Any more advice on this subject? Thanks in advance.

[barryspc]

just not sure if the inside of the mount will scratch the CPU connection on the D40 body that's all.