Double item focus

edited September 2016 Posted in » Canon T3i Forum
Hello all,

I have been having issues with focusing on two items in one photo.
Current setting is AV, and I've been using IOS between 200 and 400.

Please help.

Comments

  • edited September 2016
    To focus on two items in one photo both must be within the depth of field, which means you must stop the lens down enough. Exactly how much depends on the lens and the distance. Depth of field depends on aperture (smaller = greater), lens focal length (wider = greater) and distance (further = greater).

    There is an online program, http://www.dofmaster.com/dofjs.html which can help you determine what you need depending on what lens you're using.

    Since depth of field is greater behind the focal point than in front of it, if you want two subjects in focus, you should focus somewhat closer than halfway between the two.

    If there is no convenient point on which to focus, you may have to switch to manual focus.

    Depending on what resolution is needed for the final result, if you don't need a big print, one possible way to gain some DOF is to move back or set a zoom lens to a wider focal length even if it results in poor framing. Then crop the photo.

    Before getting too involved with complicated solutions, though, try just closing down the lens to something around f/8 or f/11, and try to focus between the two items. It may be enough.
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