[Heinrich Lohmann]

It is a manual focus "A" lens. I have had it for probably 15 years but have not used it since film days.

This morning I put it on The K100D and go for my daily walk. Every picture I take is overexposed exept when I dial in max. apt. In other words the lens is not closing down. The lens seems to be in good shape, nothing sticks and every thing is smooth.

After I come home I stick it on the K10D and guess what, it works perfect. I put it back on the K100D and it is not closing down.

Does anyone have any idea of what is going on? Your ideas will be appreciated.

Heinrich

[KungPOW]

What mode are you using? The A lenses need either TA or M.

Do you have the aperture ring set to "A"? If you want to use the ring, you need to have the camera in M mode only. In M mode, you can meter by hitting the AE-L button. In wich case, you need to set the custom settings "allow use of aperture ring" and change the AE-L button to TV shift.

Does the lens stop down when you DOF preview?

Eric.

[Heinrich Lohmann]

What mode are you using? The A lenses need either TA or M.

Do you have the aperture ring set to "A"? If you want to use the ring, you need to have the camera in M mode only. In M mode, you can meter by hitting the AE-L button. In wich case, you need to set the custom settings "allow use of aperture ring" and change the AE-L button to TV shift.

Does the lens stop down when you DOF preview?

Eric.

Eric, dial set to AV mode and aperture to "A". I use a number of Pentax "A" and "M" lenses and none of them have ever done this.

"allow use of aperture ring" was one of the first things I did when I got the camera.

Does not stop down on DOF preview

What puzzles me is, if it is the lens why does it work on the K10D?

Heinrich

[creampuff]

I had this lens but sold it to a friend who shot film. Mine consistently overexposed by 1 2/3 stops on my K100D. Had the aperture coupling lever bent ever so slightly by a camera repairer. After that the exposure was perfect when tested against a Minolta Flash Meter V.
I suspect the aperture coupling lever might be the culprit.

KungPOW, if the lens has a PK-A mount (with the A setting on the aperture ring) the lens is able to shoot at every exposure mode when set at the A setting.

[Heinrich Lohmann]

I had this lens but sold it to a friend who shot film. Mine consistently overexposed by 1 2/3 stops on my K100D. Had the aperture coupling lever bent ever so slightly by a camera repairer. After that the exposure was perfect when tested against a Minolta Flash Meter V.
I suspect the aperture coupling lever might be the culprit.

KungPOW, if the lens has a PK-A mount (with the A setting on the aperture ring) the lens is able to shoot at every exposure mode when set at the A setting.

Thank you for the info, that's what I'll do have the aperture lever worked on. Since it workes on the K10D it can't take much to fix it, thanks again for the help.

Heinrich