Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie
Hi all! We have been experiencing an issue on site where threads have been missing the latest postings. The platform host Vanilla are working on this issue. A workaround that has been used by some is to navigate back from 1 to 10+ pages to re-sync the thread and this will then show the latest posts. Thanks, Mike.
Hi there,
There is an issue with role permissions that is being worked on at the moment.
If you are having trouble with access or permissions on regional forums please post here to get access: https://www.boards.ie/discussion/2058365403/you-do-not-have-permission-for-that#latest

Sigma 20-40 DOF preview issue

  • 08-10-2010 10:03pm
    #1
    Ricky91t
    Closed Accounts Posts: 6,281 ✭✭✭


    OK,

    This is a weird issue, This just happened one day while I was shooting multiple frames, I never use the DOF preview button and probably hadn't used it for months prior to this, But while I was shooting the image started getting darked as if the button was pressed, The camera was still reading F/4 but the images looked to be shot at f/20, First it went straight to a very low aperture f/8 then f/16 and then f/20.

    It has continued to do this and makes the lens unusable, I've also got a 100-300 f/4 and 70-200 f/2.8( both sigma ) but it is just specific to my 20-40 f/2.8...

    Has anyone ever has this issue? How have you resolved it?

    Thanks


Comments

  • #2
    zerohamster
    Registered Users, Registered Users 2 Posts: 1,792 ✭✭✭zerohamster


    I cant say for sure if its a faulty diaphragm but try cleaning the contacts on the lens and camera with a rubber eraser, might do the trick.
    does the lens stay at f/20 constantly or just when you are composing? can you change the aperture at all?


Advertisement