Quick Reference for Newbie Photographers

Discussion in 'Digital Photography' started by chrismccorkle, Jul 19, 2006.

  1. chrismccorkle macrumors regular

    chrismccorkle

    Joined:
    Jun 13, 2006
    #1
    Aperture - Most lenses contain a diaphragm, a thin light-blocking plate or interleaving set of adjustable plates. The diaphragm contains a small hole, the aperture, which is adjustable in size and allows the photographer to control the amount of light entering the camera. Apertures are indicated by the f stop value, which is a relative value and does not indicate the actual size of the aperture hole.

    WIDE APERTURE:

    [​IMG]
    50mm @ f/1.4

    MID APERTURE:

    [​IMG]
    50mm @ f/8

    SMALL APERTURE:

    [​IMG]
    50mm @ f/16

    The higher the value of the stop (f/16, f/22), the smaller the hole through which light passes, the clearer the overall image is.
    The lower the value of the stop (f/2.8, f/1.4), the wider the hole is, the shallower the depth of field (defined later.)

    -------------------------------------------------------------

    Shutter Speed - The precisely-calibrated amount of time that a camera shutter stays open, usually measured in fractions of a second.

    The shutter speed and the lens aperture are the principal forms of control that a photographer has over the amount of light which hits the film or image sensor of a camera. To be more accurate, this should really be known as “shutter time,” but “shutter speed” is the traditional name.

    QUICK SHUTTER

    [​IMG]
    32mm @ 1/1000 sec (f/5.6)

    MID SHUTTER

    [​IMG]
    80mm @ 1/64 sec (f/5.6)

    SLOW SHUTTER
    [​IMG]
    28mm @ 2" (2 seconds) (f/2.8)

    Quick shutter speed allows for capturing motion in a still shot, and slow shutter speed allows for motion to be captured.

    -------------------------------------------------------------

    Aperture Priority Mode - Also “aperture preferred system.” A programmed automatic exposure setting on most automated SLRs. In this mode the photographer specifies the desired aperture and the camera automatically sets an appropriate shutter speed based on information from its internal light meter.

    Canon, Pentax and Contax abbreviate aperture priority as “Av” for “aperture value.” Nikon and Minolta abbreviate it as simply “A.”

    Shutter Speed Priority Mode - Also “shutter preferred system.” A programmed automatic exposure setting on most automated SLRs. In this mode the photographer specifies the desired shutter speed and the camera automatically sets an appropriate lens aperture based on information from its internal light meter.

    Confusingly, Canon, Pentax and Contax abbreviate shutter priority as “Tv” for “time value.” Nikon and Minolta abbreviate it as simply “S.”

    -------------------------------------------------------------

    Depth of Field - (DOF).

    Very simply the distance range of acceptable focus in front of your lens.

    When you focus your camera on a given point there is a range in front of the point and behind that point which is also in acceptable focus. If this range is very narrow then you have very shallow depth of field - only the plane at the focus point will be in focus and everything else will be blurry. If you have deep depth of field then much more of the image will be in acceptable focus.

    Examples:
    [​IMG]
    Shallow DOF

    [​IMG]
    Deep DOF​

    Depth of field is determined by a number of factors. The three key factors governing depth of field on a given camera are the aperture and focal length of the lens and the subject distance.

    Aperture.
    The larger the aperture (smaller the f stop number) then the smaller the depth of field and vice versa. Pinhole cameras, which have tiny holes rather than lenses, have a near infinite deep depth of field.

    Focal length.
    Lenses with short focal lengths (wide angle lenses) have wider depths of field available and lenses with long focal lengths (telephoto lenses) have shallower depths of field available. This is generally a good thing. If you’re using a really wide lens for landscape shots you’ll be able to get huge areas of scene in sharp focus. But if you’re using a really long telephoto lens for bird photography then your depth of field will be really shallow and you’ll be able to isolate the bird in the landscape nicely.

    [​IMG]
    Short focal length - wider DOF (more in focus)

    [​IMG]
    Long focal length - shallower DOF (less in focus) ​

    Subject distance.
    Finally, the distance from the lens to the subject also affects depth of field. If you’re really close to your subject, such as with macro photography, then depth of field will be shallow. But if you’re taking a photo of something that’s a long way away then your depth of field will be deeper.

    One other point is that the size of a camera’s image area also dictates the depth of field. A camera with a large image area - say a medium-format or large-format camera - is capable of a much more shallow depth of field than a camera with a smaller image area. This is why consumer digital cameras, which have tiny image sensors, have such deep depth of field.

    It should also be noted that this is a very non-technical description of what depth of field is all about. To be more accurate you need to go into a lot of math and consider the definition of the circle of confusion and the print size and so on. But the simplified aspects above are adequate to get a grasp of how to control depth of field adequately to make your photos look the way you want them to.

    Depth of field is sometimes called depth of focus, but that is not correct. Depth of focus would be the tiny range of acceptable focus behind the lens at the focal plane itself.

    Add additional tips below. Definitions from PhotoNotes.org
     
  2. Cybix macrumors 6502a

    Cybix

    Joined:
    Feb 10, 2006
    Location:
    Western Australia
    #2
    great, to the point guide for photo noobs.

    I love pic #4, that dog looks seriously psychotic.. kung-fu jacky!
     
  3. RedTomato macrumors 68040

    RedTomato

    Joined:
    Mar 4, 2005
    Location:
    .. London ..
    #3
    That would seem to contradict your examples, where a f/16 photo shows *more* depth of focus than a f/8 photo.

    Perhaps reword or explain a bit more?
     
  4. Applespider macrumors G4

    Applespider

    Joined:
    Jan 20, 2004
    Location:
    looking through rose-tinted spectacles...
    #4
    Great idea... as you (and hopefully others) grow it - it might be worth stickying...
     
  5. cookie1105 macrumors 6502

    Joined:
    Mar 27, 2006
    Location:
    London, UK
    #5
    I second that Applespider.

    Good beginner guide. Sweet and to the point.

    Here is a link to the morguefile classroom. It's basically a free photography tutorial. I found it very useful for learning the basics and I go back to it frequently to refresh:)
     
  6. pulsewidth947 macrumors 65816

    pulsewidth947

    Joined:
    Jan 25, 2005
    Location:
    squarefrog.co.uk
    #6
    Please sticky this! I've just stumbled upon it completely by random and there is some great advice here. Thanks for taking the time to do this chrismccorkle *round of applause*
     
  7. JonHimself macrumors 68000

    JonHimself

    Joined:
    Nov 3, 2004
    Location:
    Toronto, Ontario
    #7
    Thanks for this! I always understood the definitions but the photos are great for being able to compare them side by side. I've tried to this with my old SLR but always forget which settings I used by the time I got them developed... at least now with my new dslr I can just look at the data on the file. This thread is great though and I'll put my name on the list of people who think this is worthy of being a sticky.
     
  8. chrismccorkle thread starter macrumors regular

    chrismccorkle

    Joined:
    Jun 13, 2006
  9. seenew macrumors 68000

    seenew

    Joined:
    Dec 1, 2005
    Location:
    Brooklyn
    #9

    Chris, I've emailed and PMed you.
     
  10. Abstract macrumors Penryn

    Abstract

    Joined:
    Dec 27, 2002
    Location:
    Location Location Location
    #10
    Can anyone do something similar with Photoshop, maybe with several of the more popular editing techniques? :eek:
     
  11. Artful Dodger macrumors 68020

    Artful Dodger

    Joined:
    May 28, 2004
    Location:
    In a false sense of reality...My Mind!
    #11
    Great thread

    Thanks for doing this as I'm just starting out with my D50 and classes aren't starting for some time yet. This will really help out now and over time. Hopfully this gets made into a Sticky and will grow for all to enjoy :)
     

Share This Page