Monday, December 13, 2010

Taking Photos with Depth of Field


The heading to this should actually read, ‘Taking Photos with a Shallow Depth of Field’.  As you can imagine I didn’t write that because it’s just too confusing, since we haven’t even discussed Depth of Field (DOF).

So as to keep this simple in the true spirit of this blog, the only thing you need to know is that DOF refers to how Blurry or how Sharp your images will be.  A Shallow DOF means that there will be a lot of blur.  A Large DOF means that there will be very little blur.  I guess the best way to demonstrate this to you is to show you two images showing off the two scenarios.

A: The first image shows off a Shallow DOF.  I took this picture with my F Stop set to f/1.4 (your lens may not have f/1.4 so just set it to the lowest number, however, you may not get the same amount of blur). Notice how only a certain point on the picture is in focus and the rest is pretty much blurred.  This technique is best used to focus on a particular area on the subject.  Another way to understand it would be: “Technically/Artistically it is a way to make the viewer ‘focus’ on what you want them to see in your shot.”



B: The following image shows off a very large DOF.  Notice how most of the image is in focus.  This is best placed in situations where there are large crowds and you wish to keep all the detail in the image, Landscapes, Architecture and is very popular with holiday snaps too! ;o)


We’ll deal with the Large DOF in the next post.  So let’s take a look at how we can achieve a Shallow DOF in our shots.  One thing you need to remember is that the larger the iris (lowest F Stop number, eg. 1.4) the shallower the DOF you will get in your images.  However, this is not the only consideration for shallow DOF.  Distance is also a large factor in this.  The closer you are to the subject will also create a shallower DOF. 

Here is another example of DOF, two images side by side.  You can see that shot A has a very shallow DOF.  Notice how the blur starts very close to the sharpest point.  
Now take a look at image B and you can see that the headphones are completely in focus, however, look at the table.  As it disappears into the distance, it goes out of focus.  This is the 'distance' affecting the DOF.  We'll take a look at that more closely in the next post.


Now that we have touched on the subject of DOF, the following question maybe spinning around in your head:-

When is it best to use this?

Well there is no short or solid answer and I am loathed to give actual specific directions on where to use it.  The reason for this is that it’s your photo and it really is up to you.  Who’s to say it’s right or wrong.  That’s the beauty of it.  Take a photo and see how you feel about it.  If it feels good to you then it’s probably a good photo.  The best way to improve is to just get out there and take lots and lots of photos!

2 comments:

  1. when I use Shallow Field of Depth ( PIC B ) shutter takes longer to close and my pics and up going Blurry so I always use Option ( PIC A )
    but id rather use B, majority of these shots are taken indoors in low lighting, e.g nightclubs/parties etc

    ReplyDelete
  2. Good Question sky:

    So even if you own a 'Fast Lens' (a lens that can go very low in f/stop like f/1.4) taking pictures in low light can still be a problem. The first step in improving your situation would be to set your Apterture Speed to 1/60th minimum (any lower than this and you will need to consider a tripod) and increase the ISO. Do not go above an ISO of 1600 (above 1600 the image begins to look grainy). If this doesn't help your situation then read on.

    So a Fast Lens and a High ISO is still giving you dark/blurry images, what can you do about it? Well at this point you need to look at using a flash. If used correctly no one will know that you've used a flash. I am going to write a Post about using a flashes sometime soon.

    The type of flash you use is also key here. A cameras built in flash usually has very little options for control and does not take into consideration the length of the lens. This can cause shadows in your photos. The best way forward is to get yourself a hotshoe flash. This is a small portable unit that fits on top of your camera.

    Did this help?

    ReplyDelete