Comparing full frame to m4/3: DOF question

Discussion in 'Open Discussion' started by sprinke, Jul 4, 2012.

  1. sprinke

    sprinke Mu-43 All-Pro

    Apr 5, 2011
    Pasadena, CA
    So, I have a friend who shoots with a Nikon full-frame camera. She does food photography mostly (has a nice blog) and typically uses a 24-70mm constant f/2.8 zoom lens for her work.

    I know that due to the crop factor that would equate to a 12-35mm lens on :43:, but what would be the equivalent max aperture? Is it also halved, so would be f/1.4?

    Or to turn it around somewhat, the new Panny 12-35mm f/2.8 zoom would be like using a 24-70mm f/5.6 lens on a full-frame camera?

    Please correct me if this is wrong, and let me know how to figure out the math, or point me to a tool I can use to do it.

  2. With_Eyes_Unclouded

    With_Eyes_Unclouded Mu-43 All-Pro

    Apr 17, 2012
    Yes, two stops down.

    Correct. But all that is somewhat misleading. For example, there is not always a need for such shallow DOF. Also a FF lens may not exhibit appropriate sharpness for the application at hand, at its widest aperture.
  3. silversx80

    silversx80 Mu-43 Veteran

    Apr 27, 2012
    North Carolina
    It'd be like using a 12-35mm f/2.8 lens on a "full frame" camera, and cropping a 4/3 sensor sized area out of the middle of the 36mm X 24mm sensor.

    Use this tool to calculate your effective depth of field (Online Depth of Field Calculator), or the area that will appear to be in focus.