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645D issues

67II
Posted 16/12/2013 - 15:00 Link
Hello,

Can anyone tell me if they experience the shutter tripping when using the depth of field preview on their 645D?
I am using the Optical Preview through the viewfinder, which is the default setting. I am not using the Digital Preview. When i release the main on/off preview switch, to return to normal camera operation, the shutter sounds and appears through the viewfinder to have fired, but no image appears on the screen.

Also, has anyone experienced any issues with the focusing ring of their 55mm kit lens? If I place my thumb and index finger either side of the focus ring and gently move it from side to side there is movement in each direction of around 1mm before the ring starts to alter the focus. When the lens is taken to the stops in either direction the focus ring continues to rotate indefinitely.

Can anyone tell me if either of these concerns are inherent features of this camera?

All possible explanations gladly received.

Chris
johnriley
Posted 16/12/2013 - 15:21 - Helpful Comment Link
Many AF lenses will continue to rotate indefinitely, so I wouldn't worry about that unless you have a focusing problem.

As for the first point, the lens is stopping down and then releasing again and maybe the mechanism that controls this is making the noise. If the shutter was tripping a frame would be used and you'd know it from your file number.
Best regards, John
Mannesty
Posted 16/12/2013 - 15:49 - Helpful Comment Link
Your smc D-FA 645 55mm F2.8 lens employs the "Quick-Shift" focus mechanism. I'm not sure if the 1mm 'delay' is normal, but it is normal for the focus ring to continue turning after the min & max focus limits have been reached.

It uses some kind of slipping clutch mechanism to achieve this. Essentially, it allows you to manually adjust the focus of an AF lens having first used AF to focus initially, and without having to switch from AF to MF.
Peter E Smith - flickr Photostream
Edited by Mannesty: 16/12/2013 - 15:49
67II
Posted 16/12/2013 - 15:51 Link
John,

Thank you for your reply.

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