Ai-s

Nisio

Question on ai-s lenses if I move the aperture pin on the lens should I see the blades move? Bought a lens on eBay and suspect something up 2.8 is as bright as 22

DaireQuinlan

which aperture pin are you talking about here ? You can move the aperture ring on the lens all you like, the lens won't stop down. There's a small lever which is what you might be talking about actually on the lens mount itself which you should be able to push a certain distance (depending on how far you have the aperture ring turned). This should indeed close the aperture down as you push it.

CabanSail

As said above. The lever protruding from the back of the lens will shut the Aperture down to whatever is set on the Aperture Ring. That lever is part of the Reflex Mechanism that opens wide open when composing to allow the viewfinder to be as bright as possible. The lever is actuated to reduce the aperture during exposure to whatever is set. You can see this happen when you press the DOF Preview button.

If you have the aperture set to minimum then operate that lever, if nothing happens then the lens is a dud.



You can see the lever on the top left in this photo (From Wikipedia)

Nisio

It's a dud.

Thanks for the replies lads

Hugh_C

As a matter of interest, what body are you using it on? could be the body is incompatible with ai-s ...

DaireQuinlan

Hugh_C wrote: »

As a matter of interest, what body are you using it on? could be the body is incompatible with ai-s ...

Actually the AIS lenses are probably the most compatible of all the particular F-mount variations. They'll mount on anything, they won't meter with a pile of bodies though. OTOH, that linkage to stop down the aperture is probably the most constant thing on the F-Mount. Everything from pre-AI onwards has it, up to and including the G lenses.

Nisio

Hi Hugh,

I've tried it on a d80 and an fm2 (that has a dof lever); just doing the test of setting the lens to f22 and moving the pin myself doesn't move the blades.