Author Topic: Focus Shift with Tamron lens and Canon APS-C DSLRS - Any help?  (Read 1967 times)


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Hello Magic Lantern Forum,

     I wasn't sure where to post this issue I'm having, but here it is.

     While recording on the Canon 7D and T3i with the Tamron 17-50 f2.8 VC lens, I have had a couple times while recording H.264 1080p video (both at 23.976 fps and 29.97 fps), the exposure suddenly shifts and is darker. From what I read, this might be a focus shift issue. I'm also using a Sigma 72mm UV filter.

     Can anyone clarify what this is, if they've also had it, and if there is a solution for it?

    Here are a few links and the times with the problem:

    At around 1:50 -

    At around 5:58 -

    Thank you.

    - Paul Harwood