I'm trying to understand how adding the Dandelion chip to an old lens works in practice. I understand that the chip is programmed by the user with the focal length and max and min aperture. Am I right in thinking that operation is as follows?
- The chipped lens is mounted on the camera.
- The aperture ring is turned to minimum (but the aperture is held open by the camera aperture lever).
- The shutter is pressed.
- The camera calculates the required aperture.
- The aperture lever moves down the required distance to give the desired aperture. (Contrast this with the early film cameras: on these the lever dropped all the way, allowing the lens to close down as far as the aperture setting.)
This requires that the aperture mechanism on the lens behaves in a similar way from lens to lens.
If this is so, then how accurate would it be with, for example, a Tamron lens on an Adaptall 2 - Nikon adaptor?