150mm compared to 300mm view

Discussion in 'Native Lenses' started by RamblinR, May 6, 2013.

  1. RamblinR

    RamblinR Mu-43 Top Veteran Subscribing Member

    Aug 16, 2012
    Qld Australia
    I know when a lens goes wider just a few mm it makes a huge difference but that zooming in isn't as dramatic.

    I currently have the 40-150 oly lens still looking at getting the 100-300 pany or the 75-300 oly.

    I would really like it if someone would post the same view with the camera at 150mm and then 300mm. I want to see how much closer I am really getting if I purchase the bigger zoom.

    Much appreciated.

  2. Rudy

    Rudy Mu-43 Top Veteran

    Jan 24, 2013
    Oakland, CA
    From the same location you would be getting a picture half the size in each direction. To get the same part of the scene to fill the frame you would have to be twice as far away.
    Perspective would be different, which makes a difference to the look if there are subjects at different distances from your camera.
  3. gugarci

    gugarci Mu-43 Veteran

    Jul 8, 2012
    Lyndhurst, NJ
  4. David A

    David A Mu-43 All-Pro

    Sep 30, 2011
    Brisbane, Australia
    Rule of thumb: doubling the focal length halves the width/height of what gets included in the frame. That means that at 300 mm you include one quarter of the area you would capture at 150mm.

    Take the whole frame area of an image shot with your 40-150 at 150mm (that means no cropping) and draw 2 lines, one down the centre of the image from top to bottom and one across the centre of the image from left to right so that you have divided the image into 4 quarters. What you would capture at 300mm is one of those quarters.

    Now, to visualise what you would get at 300 mm compared to 150mm if you focus on the same spot, you have to move an area the size of one of those quarters to the centre of your 150mm image. Divide each of your quarters into quarters by drawing lines horizontally and vertically through the middle of each. The area you would capture at 300 mm is the area covered by the 4 central quarters of your original quarters so just mask off the top halves of the 2 top quarters, the bottom halves of the 2 bottom quarters, the left halves of the two left quarters and the right halves of the 2 right quarters. That leaves only one quarter of each of the original 4 quarters displayed, in the centre of the original image, and that area is what you would get at 300mm.

    You can follow the same approach if you want to see what 100 mm would give you compared to 50mm, or what 25mm would give you in comparison to 12mm.
  5. RamblinR

    RamblinR Mu-43 Top Veteran Subscribing Member

    Aug 16, 2012
    Qld Australia
    OK, thanks for that.
  6. zensu

    zensu Mu-43 All-Pro Subscribing Member

    Aug 8, 2012
    Alabama USA
    Wouldn't the 300mm also...

    give greater magnification of what is behind the subject? In other words the 300mm would pull more distant objects twice as close as a 150mm? I'm not sure which is why I'm asking.