| Other than controlling exposure, the aperture | | | | * When you want to emphasize an object in a |
| setting has another significant effect on your | | | | photo, by making everything else less focused. |
| pictures. That is, the depth of field. | | | | I've set the aperture to the smallest number. But |
| To understand depth of field, you need to | | | | I still can't get that much of a blur. |
| understand that lenses can focus at only one | | | | Different lenses have different aperture range. |
| distance. It could be anywhere between its | | | | Some can go as low as f1.2, while others can only |
| nearest focusing distance and infinity. The distance | | | | reach f4. That is why some of the professional |
| that a lens is focused at, is where objects will | | | | lenses are so expensive. Not only do they contain |
| appear the sharpest. And objects in front or | | | | quality glasses, they allow you to use very low |
| behind that focused distance will gradually become | | | | aperture numbers. But of course, there are |
| more fuzzy or blurry as their fore/aft distance | | | | inexpensive alternatives such as the Nikon or |
| increases. | | | | Canon 50mm f1.8 lenses, or f2.8 lenses from |
| The above photo is a good illustration of depth of | | | | Tamron, Sigma and Tokina. |
| field. The lens was focused on the part of the | | | | Also, the distance between you and your focused |
| barbwire that is in sharp focus, and everything | | | | distance plays a part too. At the exact same |
| else in front or behind are turned into a nice | | | | aperture setting and zoom/focal length, the closer |
| creamy blur. | | | | you move in to your subject the lesser depth of |
| Hence, you pick the appropriate depth of field | | | | field. Of course, this changes your photo's |
| depending on your needs. And you do that by | | | | composition. But it is an important knowledge for |
| setting an appropriate aperture setting. To get | | | | times when you are very close to your subject |
| less depth of field, you use a lower f-stop (e.g. | | | | (like a close-up headshot), and you are wondering |
| f1.8, f2.8), and to get more depth of field, you | | | | why only certain parts of the face is in focus, |
| simply use a higher f-stop (e.g. f8, f11). | | | | while there is no focus issue when you take a |
| When do you want large depth of field? | | | | half-body shot. |
| * When you are shooting stuffs like landscape or | | | | The simple practical approach |
| architecture, where you want everything in the | | | | Too much mambo jambo to remember? In the |
| picture to be in focus. | | | | world of digital photography, there's really no need |
| * When taking group photos. You want enough | | | | to memorize all these technical stuffs. Just go out |
| depth of field to have everyone's face in focus, | | | | and shoot, and play with the aperture setting to |
| especially when you have more than one row of | | | | achieve your desired depth of field. Move closer |
| people. | | | | or further from your subject and see how it |
| When do you want less depth of field? | | | | works out. Nothing beats learning by hands-on. |
| * When taking portrait shots, and you want to | | | | Very soon, you'll get the hang of it. |
| turn the background into a nice creamy blur. | | | | Happy shooting! |