On May 15, 2012, at 9:43 PM, John Francis wrote: > > I've run into a problem trying to use my (Vivitar) auto extension > tubes with my K-5. > > Scenarion: Camera set to "M", lens (A 50/f1.4) set to f/22. > > With the lens directly mounted to the camera, everything works as > expected: DOF preview stops the lens down to f/22, and the exposure > check showshow far I am off from correct exposure. Taking theshoot > results in an image correctly exposed at f/22. > > If I put one of the extension tubes in place, though, the lens > stays wide open at all times, and the image is captured at f/1.4 > [no other changes to the settings on either lthe lens or the body] > > This is not what I expect (or want). Any clue as to what is wrong?
Maybe the extension tube isn't moving the stop down lever. 1) Does it work with other lenses? 2) When you take a lens off, then use the depth of field preview, can you see things moving on the camera body to trigger the stop down lever? 3) When you put the extension tube on, and use the DoF preview, can you see things moving at the exposed end of the extension tube? 4) If you put the lens on the extension tube, and poke and prod with your fingers, can you get the lens to stop down? -- Larry Colen [email protected] sent from i4est -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
