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12-02-2011, 11:03 PM   #1
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K-r and Tamron AF 28-75 f2.8 lens

I just received the Tamron AF 28-75mm f2.8 lens. It has an aperture ring. The settings go from A 32 - - - - 2.8. Does the aperture ring need to be set to A at all times or can you manually pick the aperture setting you want to use. I currently have aperture ring set to permitted under the custom menu settings. I mainly use M, AV or TV capture settings. Any suggestions or answers are appreciated.



12-02-2011, 11:07 PM   #2
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You've done the first important thing - you set the menu to allow you to use the aperture ring. If the aperture ring is in the 'A' setting then the camera can control the aperture either automatically or at your direction via settings. If you put it on another setting you are manually setting the aperture on the lens. One of the advantages of the A lenses over the M lenses is the ability of the aperture to be controlled via the camera interface.
12-03-2011, 12:03 AM   #3
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To manually change the aperture you should leave the ring in A and then use Av mode to specify the aperture via the camera. No harm in allowing use of the aperture ring, but then it's pretty much going to behave like a manual lens.

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