https://community.usa.canon.com/t5/EF-RF-Lenses/Lens-changing-Live-View-s-aperture-in-Manual-mode/m-p/174240#M16193 <P>I just purchased a used 135L and have noticed on 2 different occasions that the aperature will start auto-adjusting in Live View as I increase or decrease exposure. The camera still says aperture is at 2.0 and it still renders the picture wide-open...but the live wiew will be obviously stopped down. The first time it did it, I turned the camera off and back on, and it stopped doing it. I then cleaned the lens contacts up a bit with a pencil eraser. The second time it did it, I twisted the lens off and back on, and it quit doing it.&nbsp; So at this point I am thinking it is a lens issue, but wondered if anyone has had a similiar issue? The camera is a Canon 5D Mark III.&nbsp; When I press the DOF button it switches aperture back to wide-open, but only when it is pressed (like it's supposed to). When I release it, Live View returns to it's stopped down view, while at the bottom left it still says "2.0".&nbsp; Live View should always stay at a wide-open aperture, no matter what camera settings, correct?</P><P>&nbsp;</P><P>***It's like the camera is auto-adjusting aperture to keep the Live View from over-exposing / under-exposing. Is there a camera setting that does this that I am unaware of?</P><P>&nbsp;</P><P>Thank you for reading....</P> Wed, 25 May 2016 23:25:38 GMT inick2005i 2016-05-25T23:25:38Z https://community.usa.canon.com/t5/EF-RF-Lenses/Lens-changing-Live-View-s-aperture-in-Manual-mode/m-p/174240#M16193 <P>I just purchased a used 135L and have noticed on 2 different occasions that the aperature will start auto-adjusting in Live View as I increase or decrease exposure. The camera still says aperture is at 2.0 and it still renders the picture wide-open...but the live wiew will be obviously stopped down. The first time it did it, I turned the camera off and back on, and it stopped doing it. I then cleaned the lens contacts up a bit with a pencil eraser. The second time it did it, I twisted the lens off and back on, and it quit doing it.&nbsp; So at this point I am thinking it is a lens issue, but wondered if anyone has had a similiar issue? The camera is a Canon 5D Mark III.&nbsp; When I press the DOF button it switches aperture back to wide-open, but only when it is pressed (like it's supposed to). When I release it, Live View returns to it's stopped down view, while at the bottom left it still says "2.0".&nbsp; Live View should always stay at a wide-open aperture, no matter what camera settings, correct?</P><P>&nbsp;</P><P>***It's like the camera is auto-adjusting aperture to keep the Live View from over-exposing / under-exposing. Is there a camera setting that does this that I am unaware of?</P><P>&nbsp;</P><P>Thank you for reading....</P> Wed, 25 May 2016 23:25:38 GMT https://community.usa.canon.com/t5/EF-RF-Lenses/Lens-changing-Live-View-s-aperture-in-Manual-mode/m-p/174240#M16193 inick2005i 2016-05-25T23:25:38Z https://community.usa.canon.com/t5/EF-RF-Lenses/Lens-changing-Live-View-s-aperture-in-Manual-mode/m-p/174241#M16194 <P>That's exposure simulation, not the aperture changing.&nbsp;</P> Wed, 25 May 2016 23:28:39 GMT https://community.usa.canon.com/t5/EF-RF-Lenses/Lens-changing-Live-View-s-aperture-in-Manual-mode/m-p/174241#M16194 TTMartin 2016-05-25T23:28:39Z https://community.usa.canon.com/t5/EF-RF-Lenses/Lens-changing-Live-View-s-aperture-in-Manual-mode/m-p/174244#M16195 <P>***Edit:&nbsp;&nbsp; I appreciate the help.&nbsp; I've been shooting pictures with the 5D for about 3 years now, but with only manual lenses for the past few years.&nbsp; Thank you for putting me on the right track with this, I had no idea. I'm use to the Live View being the wide-open aperture no matter what.&nbsp; Live and learn!</P><P>&nbsp;</P><P>Thanks again!</P> Thu, 26 May 2016 00:08:08 GMT https://community.usa.canon.com/t5/EF-RF-Lenses/Lens-changing-Live-View-s-aperture-in-Manual-mode/m-p/174244#M16195 inick2005i 2016-05-26T00:08:08Z