Gigi, the effect becomes less obvious the further away the subject is. With a 50mm lens at f/8 for example, focussing at 20 feet gives a dof from 14.4 to 32.6 feet, i.e. a long way in front and behind the subject. Focussing at 5 feet, as for a portrait possible, gives a dof from 4.5 to 5.5 feet, i.e. only six inches in front and behind the focus plane..

So if you have tried your experiment with something relatively distant from the camera you won't see the effect as clearly as you would if you use a subject much closer to the camera..

Also - focal length makes a big difference. Wide angle lenses have a much larger depth of field than tele lenses, so if you did the test with a wide angle lens then try repeating it at a longer focal length. For example: at 18mm, and a subject distance of 5 feet at f/8, the dof extends from 2.9 to 19.5 feet!! So at one end of your standard zoom the dof is 2.9 to 19 feet; at the other ened it is a mere 4.5 - 5.5 feet. You can guess how limited the dof would be for a close-up using a 200 mm lens....

I got the numbers above from the on-line dof calculator at.

Http://www.dofmaster.com/dofjs.html.

Best wishesMike..

Thanks Mike, for the reply. That depth of field calculator link is a great resource! I will definitely try different combinations to see what I get..

The other thing I'm a bit confused about is the focal length. From what I have read, the smaller the number (e.g., 18mm), the wider the lens and the larger the number (e.g., 200mm), the higher the telephoto? Is that correct? I think part of my problem is that I am still thinking in terms of P&S where zoom is the only thing that "matters". It doesn't help that I nearly failed physics in high school either!..

Yes, a low-numbered focal length gives a wide angle of view, and a larger number is more zoomed-in (telephoto)..

Also, I'm surprised you say you're getting a dark or blurry picture. A large aperture (low f/ number), will tend to result in light, rather than dark photos..

Try the camera at f/5.6 or however low it will go, at the 55mm end of the kit lens' zoom. Choose an object quite close to you, but distant from the background...

Read the artical then click on the "x" on the to right corner.Xttp://www.tamroneurope.com/Schaerfentiefenvergleich.289.0.html?&L=0&L=2..

Setup some test shots. Try a railing or line up some bottles or something. Shoo thte scene with various apertures.Don't wait for the Nikon D-whatever, have fun now!http://www.flickr.com/photos/j_wijnands/..

Some thoughts-.

-try this web site. the article to read is the 3rd on down.http://www.shortcourses.com/.

-dof and lenses. the longer the focal length towards 1000mm the less dof any lens will inherantly have; the reverse-the shorter the focal length towards 10mm the more focal length the lens will inherently have; AT ANY CONSTANT FSTOP..

If you want lots of dof you do not use a 1000mm lens at f2.09THE PRICE OF THE LENS WOULD BE ABOUT $100000)..

The reverse. if you use a 14mm lens you do not use it at f16.0 if you are trying to get rid of dof..

-you said some of your shot are coming out black if you do get enough dof. you must remember that for ANY PICTURE YOU MUST HAVE ENOUGH LIGHT TO BE PROPERLY EXPOSED. if you nare stopping way down to get lots of dof you must compensate in the exposure by upping the iso or lowering the shutter speed to keep the same amount of light the same. if the shot is coming out blurry then your shutter speed if too low. do not go below 1/60sec unless your lens has vr or you are using a tripod. do not go below 1/10sec period unless you have tripod..

- you need some basic photography info. I super strongly suggest that you read the above mentioned website and any others like it that you can find...

Thanks everyone for all the tips and links so far; it's going to take me awhile to digest everything. Today, I'm picking up the 50-200mm VR lens so perhaps things might become a bit more obvious to me with a larger focal length...

Aperture, focal lenght, distance from the subject, the quality of lens, type of background, lighting etc will affect the final feel of DOF. Hence you may need to experiment a little bit to get the best out from your gear....http://budding-nature-photographer.blogspot.com/..