CJ Han Offline Upload & Sell: Off
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So, in pursuing a problem encountered on a very precise shoot, with a 5DSr and Otus 85mm 1.4, I pursued 4 different avenues of Canon support, none of which could identify what I was describing; 2 different phone calls to 2 different tech reps at CPS, tech reps at the Canon EOS counter at the recent Photo Expo show in NYC, and 2 techs at the Canon CPS booth at the same show. Fair to say I felt I exhausted all “official” Canon support channels, short of dropping the camera off for in-warranty repair, and losing time.
I described the problem to Zeiss in Germany, and their tech was the only one who instantly, fully understood the operation of all Canon EOS bodies, and EF lenses, and hence Zeiss ZE mounts for Canon, with respect to Live-View operation, which addressed my out-of-focus problem. I don’t like at all how Canon has implemented “live-view” functionality, causing any lens’s diaphragm to automatically stop-down to ambient lighting conditions, despite how the camera’s set to record an image, but it is what it is. Ironic they (Zeiss) knew instantly, and the people who make, sell, and support the camera kept talking to me like I don’t know what I’m doing. Anyway, for anyone who’s trying to do very demanding, hi-res work, and using Canon’s “live-view”, here’s the procedure which MUST be followed (care of Zeiss) to get critically sharp images:
“From my point of view, I see the following details:
-It´s not a lens performance problem, it is just a focusing issue
-when focussed perfectly in live view mode with the pre-selected aperture, the resulting image is sharp exactly on the detail you have focussed to before.
I´m sure you are aware that you have to follow the following procedure for perfect focusing in live view mode with every Canon EOS camera body (and any EF mount lens attached) from a tripod:
-pre-select the largest aperture of the lens (f/1.4 with the Otus) in Av or M mode
-start the live view mode with the button
-use the maximum focus magnification
-PRESS THE STOP-DOWN BUTTON ON FRONT OF THE CAMERA TO FORCE THE EOS BODY TO OPEN THE APERTURE EXACTLY TO THE PRE-SELECTED VALUE (otherwise the camera always stops down the lens randomly according to the lighting conditions and the camera (ISO) settings)
-focus precisely to the desired detail in maximum focus magnification and f/1.4
-release the stop-down-button on the camera. Set another f-stop on the camera if you do not want to shoot a f/1.4.
-release the shutter.
If this procedure does not allow you to achieve a perfectly focussed image with any lens, there must be something wrong with the camera body.
Using the stop-down button on the camera in live view mode is essential, otherwise it is impossible to focus exactly when the camera had closed the iris randomly before.
According to the details you provided so far, there is nothing wrong with the lens itself”.
End of quote from Zeiss. The procedure the rep described above is what I ended up using myself, just to get through the shoot, all the while saying “this is crazy – it must be wrong”.
But no; sadly it’s correct.
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