DOF Question?

Discussion in 'Photography Beginners' Forum' started by Hardrock, Sep 19, 2009.

  1. Hardrock

    Hardrock TPF Noob!

    Joined:
    Apr 8, 2009
    Messages:
    1,173
    Likes Received:
    36
    Location:
    Dallas
    Can others edit my Photos:
    Photos NOT OK to edit
    Probally a stupid question but obviously when using a macro lense at f2.8 the depth of field is very shallow due to the working distance between the lense and subject, correct? So does that mean when using a telephoto like a 200mm or 300mm at f2.8 does the dof of field increase?
     
  2. chris

    chris TPF Noob!

    Joined:
    Jun 20, 2003
    Messages:
    271
    Likes Received:
    22
    Location:
    Scotland
    Other way round, for a given aperture the depth of field reduces with increasing focal length.

    Check out a DOF calculator such as Online Depth of Field Calculator.
     
  3. Hardrock

    Hardrock TPF Noob!

    Joined:
    Apr 8, 2009
    Messages:
    1,173
    Likes Received:
    36
    Location:
    Dallas
    Can others edit my Photos:
    Photos NOT OK to edit
    So basically yes if Im reading it correctly. Using a 100mm at 10in from the subject gives you a .02in dof and at 10ft a .32ft dof. So the further the subject the more the dof increases.
     
  4. Plato

    Plato TPF Noob!

    Joined:
    Jul 11, 2009
    Messages:
    1,058
    Likes Received:
    1
    Location:
    United States of America
    Can others edit my Photos:
    Photos NOT OK to edit
    Here's more detail than you ever want to know!
     
  5. Hardrock

    Hardrock TPF Noob!

    Joined:
    Apr 8, 2009
    Messages:
    1,173
    Likes Received:
    36
    Location:
    Dallas
    Can others edit my Photos:
    Photos NOT OK to edit
    Thanks guys! I think I understand now its the subject to camera working distance not the focal length that affects the dof. So with any lense at f2.8 the further you are from the subject the more dof you will have.
     
  6. epp_b

    epp_b No longer a newbie, moving up!

    Joined:
    Aug 22, 2008
    Messages:
    2,135
    Likes Received:
    12
    Location:
    True North Cold and Freezing
    Can others edit my Photos:
    Photos OK to edit
    Actually, it's the decrease in focus distance caused by the increase in focal length. Longer focal lengths typically mean that you focus closer. Macro lenses focus extremely close and, therefore, have depths of field measured in microns.
     
  7. Samanax

    Samanax TPF Noob!

    Joined:
    Jan 1, 2009
    Messages:
    2,562
    Likes Received:
    0
    Location:
    Kaneohe, Oahu
    Can others edit my Photos:
    Photos OK to edit

Share This Page