| For some time now I have been reading reports | | | | a photograph using a small focal length setting. |
| about this and trying to figure out how it should | | | | You want and expect to see more depth of field |
| influence my digital photography. | | | | in the second photograph - all the way from the |
| The basic question is: Does a wide angle lens | | | | flower in the foreground to the sunlit mountain |
| (smaller focal length) provide more depth of field | | | | peeks. And that's what you appear to get. |
| than a telephoto (longer focal length) lens? | | | | Will it cross your mind that if you blow up a |
| This has been taught to us in the textbooks and | | | | section of the second photograph that you will |
| the photo magazines for a long time and it | | | | lose all that apparent depth of field? No, the |
| appears that you get more depth of field with a | | | | greater depth of field still appears to be in the |
| wide angle lens than you do with a telephoto lens. | | | | photograph taken with the wide angle focal length |
| If you search the Internet for "depth of field", | | | | setting. |
| you will not look long until you come across many | | | | You zoomed out so that you could get a wider |
| articles that say that using a wide angle lens does | | | | view and a larger depth of field or at least the |
| not increase depth of field. | | | | perception of more depth of field. You also knew |
| Tests have been conducted by many, including | | | | that the images would appear smaller. |
| some of the photography magazines, that prove | | | | Same for zooming in, you wanted to make the |
| that depth of field is not dependent on the focal | | | | image appear larger and you also knew that there |
| length of the lens being used. | | | | would be a perception of less depth of field. |
| This is a very technical issue and technically it is | | | | From a practical point of view when you change |
| true. You can even conduct similar tests or | | | | focal lengths seldom if ever, will you zoom in or |
| experiments to verify it for yourself. However, | | | | out with the idea in mind of keeping objects the |
| from a practical standpoint what does this mean | | | | same size. |
| to me, the photographer? | | | | Using different focal lengths, zooming in or out, |
| All of the information that I have seen so far is | | | | gives the perception that depth of field changes. |
| based on the hypothesis that you keep the image | | | | What you get with the wide angle lens appears to |
| size the same. | | | | have more depth of field than what you get with |
| The test goes something like this: using a zoom | | | | the telephoto lens. |
| lens, take a photograph of some subject using a | | | | Technically this may not be the case. |
| telephoto or long focal length setting. Then zoon | | | | But, what is all of your photography about? The |
| out to a wide angle or shorter focal length setting. | | | | main answer is: what appears right to you. So, I |
| You could also do this with interchangeable fixed | | | | say unless you are a stickler for technical |
| focal length lenses, one telephoto lens and one | | | | correctness stick with the old time proven rule. |
| wide angle lens. | | | | · If you want more depth of field, or you |
| Now, enlarge some section of the photograph | | | | want it to appear that way, use a shorter focal |
| taken with the wide angle setting so that the | | | | length lens or zoom out. |
| image in that section is the same size as the | | | | · If you want less depth of field and a |
| image in the identical section of the photograph | | | | larger image of some part of the scene, zoom in |
| taken with the telephoto setting. | | | | to a longer focal length setting. |
| Upon examining the resulting photographs, you will | | | | This will still give me the photographic results that |
| find the depth of field is approximately the same | | | | I want. I have taken a beautiful photograph of a |
| in each of the photographs. There is basically no | | | | mountain scene and my zone of sharpness |
| difference. So, you have proven that technically | | | | appears great. |
| zooming out to a wide angle focal length did not | | | | To me this technical revelation does not change |
| increase your depth of field. | | | | the way I take my photographs. What about |
| But, let me ask you a question. Why do you | | | | you? |
| zoom out or switch to a wide angle fixed focal | | | | After all, this is your art that you are creating. |
| length lens in the first place? | | | | Don't let the pure technical explanation get in the |
| Suppose that you are standing out before some | | | | way of you creating what you want to create. |
| great mountain scene that is beautifully lit with | | | | Continue to pretend that a wide angle lens gives |
| sunrise colors. You zoom in to a telephoto setting | | | | you greater depth of field than a telephoto lens. |
| and take a picture. Then you zoom out and take | | | | Your results will show it. |