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07-07-2017, 12:21 PM   #1
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Question about the Sigma 28mm f2.8 Wide II

I just picked up a Sigma 28mm Wide II for my K70. When I control the aperture with the camera it shows a maximum f-stop of 4.0. As I stop down the lens, the camera shows all of the mid-range f-stops that are not available on this lens. Is this normal? When the aperture reads 4.0, is it really 2.8? Should I start using the aperture ring instead?

I really love this lens! It's sharp and the colors are great. I never came across this issue when I was researching the lens.

07-07-2017, 12:37 PM   #2
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Clean the contacts on the back of the lens. If that doesn't work try wiggling the lens in the mount.

As for F-stops not available...it doesn't matter to an A lens what is marked on the aperture ring.
07-07-2017, 12:50 PM   #3
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That worked! Thank you. As for the mid aperture settings, what would the aperture be if the camera gives a reading that isn't available on the lens? For instance, if it reads 20 but the lens should go from 18 to 22?
07-07-2017, 02:15 PM   #4
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The aperture on an A lens can be anything. The camera can be set for 1/3 stops instead of 1/2 stops.

07-09-2017, 10:16 AM   #5
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What the camera reads are jsut numbers. I had a Tokina 2.8/35-70 long ago with wrongly aligned aperture lever. it always read 2.4 in the camera. Unless the aperture lever is stuck, the camera will meter fine and adjust apeture on the lens to the correct closing. The steps displayed by the camera make sense even though they are not printed on the lens. Between f/16 and f/22 you can get f/18, f/20 as thirds of a full stop.
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