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06-22-2011, 01:11 PM   #1
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Vivitar 24mm 2.8 Perfect Pentax M42 Wide-Angle lens | eBay

06-22-2011, 01:20 PM   #2
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Also am I suppose to hold(ROLL) the M up will using the aperture?
06-22-2011, 01:30 PM   #3

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That lens is a T4 mount lens, with a T4-to-M42 adapter.

Push the latch in, turn the adapter in the "O" direction to remove (open) the adapter, "L" to lock.

For more details, do a search for "T4 mount" or "TX mount."

(TX mount is similar to T4 mount, but can accommodate full aperture metering).

Last edited by SOldBear; 06-22-2011 at 01:37 PM.
06-22-2011, 02:01 PM   #4
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Yep, the O-L is for the mount. Make sure that little tab is "up" and the lens is locked into the mount

The A-M switch (auto-manual) will be an "instant" switch, either opening or closing the aperture blades. It will need to be towards the M position for the aperture to close.

Some people prefer setting the aperture with the lens on A, focusing, then flicking the switch over to M to meter in Av mode and shoot the picture. Others prefer keeping the lens in M and opening it to max aperture, focus, then count the clicks to move the aperture ring to its desired f/stop.


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