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Sigma 20-40mm lens

ISP123
Posted 05/07/2018 - 20:55 Link
I have a Sigma 20-40mm wide angle lens which I have not used for a few months, when attached to my KP looking through the viewfinder it shows the image very dark. Any help out there.

Ian
Defragged
Posted 05/07/2018 - 21:43 Link
Is the aperture stuck closed down?
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ISP123
Posted 05/07/2018 - 22:28 Link
Not quite sure what you mean, forgive my ignorance
Defragged
Posted 05/07/2018 - 23:51 Link
ISP123 wrote:
Not quite sure what you mean, forgive my ignorance

The aperture blades in the lens. Are they wide open (large aperture) or closed down (small aperture) I just wondered that as you haven't used it in months if the aperture blades are sticking.
Also just check that it is mounted correctly and locked. I suspect it's something and nothing. Do your other lenses work ok?
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What you need are lenses, more lenses, bigger lenses, better lenses, faster lenses, vintage lenses and when you have these, your pictures will be perfect!
ISP123
Posted 06/07/2018 - 00:12 Link
My other lenses work fine, they are closed down
Defragged
Posted 06/07/2018 - 00:53 Link
I feel pretty sure that it's a sticky aperture blades problem. Try gently tapping the body of the lens whilst the camera is switched on and see if that causes the aperture blades to move. Set it at its widest aperture first ie 2.8 and if that doesn't work try different aperture settings.
C.O.L.B.A.S victim
(Compulsive Obsessive Lens Buying Addiction Syndrome)

What you need are lenses, more lenses, bigger lenses, better lenses, faster lenses, vintage lenses and when you have these, your pictures will be perfect!
Edited by Defragged: 06/07/2018 - 01:18
Defragged
Posted 06/07/2018 - 18:35 Link
Did You get your problem sorted out? I've just been looking at one of these lenses and now realise that it has an aperture ring. With the lens off the camera, can you move the aperture blades by turning the aperture ring or use the lever at the base of the lens to see if the blades move freely or are locked up.
C.O.L.B.A.S victim
(Compulsive Obsessive Lens Buying Addiction Syndrome)

What you need are lenses, more lenses, bigger lenses, better lenses, faster lenses, vintage lenses and when you have these, your pictures will be perfect!

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