Weekly Photo Challenge: Focus


Great photography is about depth of feeling, not depth of field. – Peter Adams

Peter Adams may be right but changing the Depth of Field can be quite useful in some cases; sometimes it may be desirable to have the entire image sharp, in which case large DOF is appropriate.

Take Your Litter Home

In other cases, a small DOF may be more effective, emphasizing the subject while de-emphasizing the foreground and background.

Spring Buds

Depth of Field can be altered by changing the Aperture in your camera.  Here’s the technical bit;

Reducing the aperture size increases the depth of field, which describes the extent to which subject matter lying closer than or farther from the actual plane of focus appears to be in focus. In general, the smaller the aperture (the larger the number), the greater the distance from the plane of focus the subject matter may be while still appearing in focus.

Aperture_diagram.svg
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. Attribution: Cbuckley at the English language Wikipedia

So at f4 the DOF will be very small, at f22 the DOF will be large. To show you this I’ve conducted a little experiment, photographing the same scene several times whilst changing the the aperture from f4 to f22.

For this experiment I’ve drafted in Edna and Mabel to act as subjects. Mabel will be in front and throughout the sequence of photographs I will maintain the focus point of my camera on her face. To avoid camera movement it’s mounted on a tripod.

Weekly Photo Challenge: Focus

In the photograph above the aperture is set at f4. As you can see, Edna, who is in the background is out of focus.

14a Focus

Now the aperture is f8, notice how Edna is starting to come into focus. Her features are much more clearer, you can even see her pudgy little nose.

14b-Focus

At f22 the photograph is in sharp focus from front to back including the fence behind Edna. In other words at f22 I have a large Depth of Field.

Every time someone tells me how sharp my photos are, I assume that it isn’t a very interesting photograph. If it was, they would have more to say. – Anonymous

On a practical note for most of my landscape photographs I tend to use f8,  f11 or f16, very rarely do I use f22. There’s a reason for this. If you look at the aperture diagram you can see that the higher the aperture number the smaller the whole is. In combination with variations of shutter speed, that hole controls the light reaching the sensor on my camera. Typically, a fast shutter will require a larger aperture to ensure sufficient light exposure, and a slow shutter will require a smaller aperture to avoid excessive exposure. So If I set the aperture to f22 I would need to have a slow shutter speed, which in turn means I could end up having blur due movement; me holding the camera, the wind moving trees or vegetation, clouds across the sky.

 

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24 thoughts on “Weekly Photo Challenge: Focus

  1. Lynne Ayers August 25, 2013 / 19:42

    I find apertures and F-stops so confusing, though you have explained and illustrated it well – perhaps I’m meant to stick with my point ‘n’ shoot.

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    • Mike Hardisty August 25, 2013 / 19:57

      I don’t find them too confusing, it’s just sometimes I choose the wrong one..

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  2. Patti Kuche August 25, 2013 / 23:13

    A very informative post thank you Mike and brilliant pictures to illustrate the differences! Your first shot is so exhilarating!

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    • Mike Hardisty August 26, 2013 / 00:10

      Hi Patti, first shot is from the Peak District last week. I really should do more informative posts..

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      • Patti Kuche August 26, 2013 / 05:31

        Yes, you should do more informative posts! You have a certain ease of style and that is good!

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  3. petspeopleandlife August 26, 2013 / 00:40

    I am astonished each time that you post a scene from Wales. You have yet to post a so-so photograph. Beauty is literally at your fingertips. And this is a really nice post for anyone that does not understand depth of field. You are a teacher as well as a gifted photographer.

    Like

    • Mike Hardisty August 26, 2013 / 15:06

      I suppose that I am lucky to live in a beautiful part of the country, Yvonne. Talking of photos you should see the ones I reject..

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  4. mhdriver August 26, 2013 / 01:19

    Well put. It is hard for some of us to understand that concept.

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  5. compostingwords August 26, 2013 / 02:19

    Depth of feeling – I like that! Thanks for the great explanation of depth of field as well.

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  6. RJ Silva August 26, 2013 / 02:35

    Wow! Thanks for the very informative post. Now, if only my camera came with such settings…

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  7. redstuffdan August 26, 2013 / 09:15

    Bonjour

    Stunning picture – like your stuff enormously – thanks for sharing it with us.

    Regards

    Dan

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  8. mithriluna August 26, 2013 / 13:06

    Thanks Mike! Very informative and wonderful images! I also like your theme. It really shows off your photos.

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    • Mike Hardisty August 26, 2013 / 15:18

      Now and again I change the theme. It’s a balance between showing the photographs and getting the word across.

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  9. Chas Spain August 26, 2013 / 14:58

    Beautiful image with the light cast in the middle distance on the valley.

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    • Mike Hardisty August 26, 2013 / 15:21

      One those grab shots Chas and being in the right place at the right time. I was actually photographing some weird rock formations behind me. Turned round, saw this scene with the sun and thought its got to be a photograph…

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      • Chas Spain August 27, 2013 / 11:50

        I love that when you’re focussed on something (even mowing the lawn) and then look up to see the light doing something clever and unexpected. Being outside is always a good start.

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  10. giberson9 August 26, 2013 / 15:54

    Just starting to learn all this! Very informative and you made it easy to understand. Thanks!

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    • Mike Hardisty August 26, 2013 / 20:58

      I’ve been thinking about doing some more easy to understand techniques, glad you liked this one and thankmyounfor commenting

      Like

  11. sustainabilitea August 26, 2013 / 16:37

    Mike, excellent explanations and I love your first two photos. I was blessed to visit Wales for a short while not many years ago and found it beautiful indeed.

    janet

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    • Mike Hardisty August 26, 2013 / 21:01

      Hello Janet. Wales is indeed beautiful, one of the reasons I moved here.

      Like

  12. Ishaiya August 27, 2013 / 20:49

    Wow! This is breathtaking. It’s like a painting that I would most definitely hang on my wall. Beautiful! Thanks for sharing 🙂

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    • Mike Hardisty August 28, 2013 / 06:53

      Thank you for taking the time to comment. I was lucky with this one, photographing something else, turned round and saw the way the sun was shining on the valley below..

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      • Ishaiya August 28, 2013 / 09:04

        Some of the best photos are the spontaneous ones, brain doesn’t interfere too much! 😉

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