How do I get a wide DOF

[agentm]

I upgraded from a G3 and now have a 10D. One thing I noticed from many of my stunning in-focus G3 photos compared to the new DSLR I have is the DOF.

How can I get the same result with the Canon 10D? E.g: How do you take a picture of a person 5 feet from you but also have the building behing her in focus?

Thanks!

[Scottes]

Generally the large DoF is achieved by using a smaller aperture. The smaller the aperture the larger the DoF.

However there is also a method where you set the lens to it's Hyperfocal Distance. The HD is the distance where everything from about 1/2 that distance out to infinity is in focus. For instance, on a 10D with a 17mm lens set at f/8, the HD is 6.24 feet. So focus the camera at something 6.24 feet away and everything will be in focus from 3.12 feet out to infinity.

The HD gets larger as lenses get larger. The HD for a 50mm lens at f/8 is 54 feet. For a 400mm lens at f/8 it's 3,453 feet.

So setting HD is good for wide-angle lenses, but probably not so useful for longer lenses. Of course, you could set the aperture smaller - HD for the 50mm at f/16 is 27 feet...


Check here for some more info, some great calculators, and some absolutely awesome Chartmakers to print custom charts to put in your bag. By the way, the Circle of Confusion, or CoC, is 0.019 for a 10D - you'll need that number for some of the calculators and charts.

http://www.johnhendry.com/gadget/index.htm

[agentm]

thank you for your help. I know about setting the aperture value larger and that this will expand the DOF, but the result in some of my photos is that the photo is darker.

The other info you gave is new to me and I will study into it more.

Thanks again

[gsmx2]

In addition to smaller apeture, a wider angle lens will expand DOF. So if you have the 18-55 lens, go to 18 and get closer to fill up the frame rather than zooming to fill it up.

gsm x2

[robertwgross]

There is a standard nature shot that I practice with a wide angle lens. I crank the aperture to the highest number on the lens and then back off one. That generally requires a slow shutter, so a tripod is required. I end up with wildflowers in focus at four feet and everything else in focus out to the horizon. That's wide Depth of Field. It is easier if you think of it as Depth of Focus.

---Bob Gross---

[stopbath]

I know about setting the aperture value larger and that this will expand the DOF, but the result in some of my photos is that the photo is darker.

:shock:
When changing aperture, you MUST compensate some how to retain the same exposure!

If your metering suggests f8 at 1/250, but you want to move to f16, you must increase the time the shutter stays open by selecting 1/125.

When you compensate correctly for the change in aperture, your exposure will remain the same, even though you are using different shutter speeds and aperture...

[4walls]

I know about setting the aperture value larger and that this will expand the DOF, but the result in some of my photos is that the photo is darker.

:shock:
When changing aperture, you MUST compensate some how to retain the same exposure!

If your metering suggests f8 at 1/250, but you want to move to f16, you must increase the time the shutter stays open by selecting 1/125.

When you compensate correctly for the change in aperture, your exposure will remain the same, even though you are using different shutter speeds and aperture...
Shooting in the Av mode should compensate for this... when you change from f4 to f8, the shutter speed should drop automatically.

[Jesper]

I know about setting the aperture value larger and that this will expand the DOF, but the result in some of my photos is that the photo is darker.

:shock:
When changing aperture, you MUST compensate some how to retain the same exposure!

If your metering suggests f8 at 1/250, but you want to move to f16, you must increase the time the shutter stays open by selecting 1/125.

When you compensate correctly for the change in aperture, your exposure will remain the same, even though you are using different shutter speeds and aperture...

Note that f/16 is TWO stops slower than f/8 (f/8 - f/11 - f/16), so you should make the shutter speed 2 x 2 = 4 times slower. So if you, at f/8, need a shutter speed of 1/250, you will need 1/60 at f/16 (not 1/125).