Forum Home
» Photos, Photos, Photos
» Photography Lessons
» Understanding Depth Of Field (DOF)
| March 16th, 2007 06:05 PM | |  LVE
Joined: Aug 1, 2006
Posts: 824 | Understanding Depth Of Field (DOF)
Depth Of Field (DOF)
I have had more discussion on this topic than any other subject. This is primarily because a lot of people shoot in Auto Modes, and what the mode delivers is what they get. If one has the capability to shoot in other than an Auto Mode, like Aperture, Shutter or Manual, they will immediately begin to see significant improvement.
When one looks at potential shot, they are usually looking at something that is three dimensional. The camera sensor however, sees and records what the photographer saw, in two dimensions with a single plane of sharp focus. If you focus on an object a fixed distance from the camera, everything at that distance will be in sharp focus, and everything not at that distance will appear less sharp. What is important to note is that there is an area in front of, and in back of the sharp focus area that is perceived to be in focus. This range in front and back of the prime focus area is referred to as the DOF. The factors that affect the amount of the DOF are:
Focused Distance – Focal Length of the shot – Camera Aperture setting.
Listen to this carefully:
If you keep the focal length constant, say 35 mm and you keep the distance to the subject constant, say 20 ft, and you open the aperture (Smaller F stop), the DOF will become shallower. This is assuming the Shutter Speed also remains constant. This means that a smaller portion of the shot will be in clear focus or have Less DOF!
Smaller Aperture # = less DOF
Conversely, larger Aperture # with the same settings of focal length, distance and shutter speed will result in greater DOF.
As a simple “rule of thumb” think - SMALLER APERTURE (Larger F Stop #)& SLOWER SHUTER SPEED = MORE DOF! This translates to LESS LIGHT LONGER
Conversely, LARGER APERTURE (SMALLER F Stop #) & FASTER SHUTTER SPEED = LESS DOF.
There will be a follow up to this!
| | | [1] | | | March 16th, 2007 08:34 PM | | LVE
Joined: Aug 1, 2006
Posts: 824 | JACK
I do remember this and this is an excllent suggestion. I think that people are always soeager to go out and take a sho of a real life situation that they never take time to do the experiment you suggest. Several years ago, I thought I was having a problem with the focus on my 1st digital camera. I met this old guy on the Internet, and he gave me an excercise to do to determine. If I ever have problem, like I recently had wit my new camera, I follow his recommendations. I also have some other bellweathers in my yard, where I can try things out and knowing what the look like, how far they are away, what the lighting typically is, I take my drink and go to my workshop. Coffee in the morning, and some stronger libations in the early evening.
Your example is very easy to follow! | | | [1] | |
Login Now to post a reply
(You will be brought back here to post your reply) |
Who's Online: Birdlady |
|
|
