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11-25-2012, 05:59 PM   #1
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shaolen's Avatar

Join Date: May 2012
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Aperture ring and zooming

So I had an FA 28-200 lens which used a manual aperture ring. If i have it on "A" on the ring and then zoom in, my aperture will get smaller as I zoom which is normal, but what happens if you leave it on the largest aperture and then zoom in? I tried it once and the picture was infact brighter but I didn't notice a difference in the bokeh. Is this bad for the lens? And why if you can leave it on the max aperture and then zoom would they make it so if you have it on A, it would get smaller as you zoom?

11-25-2012, 06:17 PM   #2
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The camera cannot read the aperture if the lens is not on the 'A' setting. You can make it work by putting the camera in 'M' mode and metering using the green button.

If you take it off 'A' and set any aperture the lens will stay at that aperture. If you zoom and it is set on the maximum aperture the lens will change to whatever the maximum is for that zoom setting as you zoom out.

It won't hurt the camera or lens but the camera will not be able to meter properly when the lens is not set to 'A'. (Unless you meter manually using the green button)

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