Originally posted by IchabodCrane All that you've missed is the ability to set the aperture ring on those A lenses and have the camera know where it's set. Instead, you have to leave the aperture ring set to "A" and then set the desired aperture on the camera. Pressing the "green" button then provides the camera with the estimated exposure.
This explanation makes it confusing.
Pressing the "green" button . . . :
Not really; that's only true with M lenses (and A lenses when the aperture ring is NOT set to "A").
And in this case you won't see the set aperture in the VF, and it's also not in the Exif.
But with A lenses (aperture ring set to "A" and control from the body), handling and behaviour is not different from any newer non-AF lens.
This includes showing the aperture in VF and Exif.
And no "green" button needed.
---------- Post added 08-11-15 at 18:23 ----------
Originally posted by reh321 I've been using those lenses exactly as I did when they were new (except that focusing is a tad more difficult):
I set aperture on the lens, put the camera in Av mode so the camera will set a shutter speed, and then I compose the picture, focus, and press the shutter button.
I didn't realize it was supposed to be more complicated than that.
If you do it this way, the camera will use even an A lens as if it was a M lens (because aperture ring not in "A" position).
The pictures may be (randomly) correctly exposed, but the metering was not done correctly.