Zeiss Loxia 25mm f/2.4: Aperture Ring Malfunctions, Making Magnified Live View Impossible, Exposure Impossible
UPDATE: I think I might have prematurely blamed the Loxia. Turns out that the Voigtlander 65mm f/2 APO-Lanthar is also showing a flaky aperture ring problem, and that the Loxia is working OK on the Sony A7R IV. In other words, the blame looks to lie with the Sony A1. That said I have had sporadic trouble with the Loxia on the A7R IV in the past.
Over the years I’ve had a few sporadic reports from Zeiss lens users of aperture rings going bad.
Now I’m seeing it firsthand with the Zeiss Loxia 25mm f/2.4.
- Entering magnified Live View immediately exits; the camera senses that the aperture is being changed.
- Taking an exposure won’t work;. The aperture readout in the camera flickers, as if the camera is continually seeing an aperture change.
I conclude that the aperture-sensing mechanism inside the lens is flaky.
These symptoms were happening intermittently but now they are more or less constant, so a lens comparison I shot just a few days ago was viable with several efforts. But I was unable to get the lens to work yesterday.
I suppose the contacts could be masked over for temporary use so that the lens acts like a "dumb" lens, but this needs to be fixed.
Classic all-mechanical lenses like the original Zeiss ZF series were pretty awesome in having essentially zero points of electronic failure, unlike “chipped” lenses (all current Zeiss offerings, Sony, Sigma, almost everything). Modern cameras systems have failure designed-in, since elecronics never last for decades; sooner or later parts go bad.