Depth of Field

I recently purchased a Cannon PowerShot A520 digital camera. I've
gotten pretty good with using many of the features, but I'm still
having a hard time in getting the right "depth" of field shots to look
like the background is blurred and the focus is on the object/person in
front.

Do I have to get a pricey SLR to achieve this effect.

Please advise....

Thanks,

Vonni

wrote in message
ups.com...
I recently purchased a Cannon PowerShot A520 digital camera. I've
gotten pretty good with using many of the features, but I'm still
having a hard time in getting the right "depth" of field shots to look
like the background is blurred and the focus is on the object/person in
front.

Do I have to get a pricey SLR to achieve this effect.

Please advise....

Thanks,

Vonni


Hi.

You will need to experiment with the camera. The small sensor cameras have
a large Depth of Field.

The Maximum Aperture setting will reduce the Depth, the longest Focal Length
will also reduce it, and the closer the subject is to the Camera will also
reduce it.

The larger the sensor, the smaller the DoF. so APS size or Full Frame might
be the way to go.

Before anyone nit-picks, it is not actually the sensor which determines DoF
it is the focal length of the lenses, but those are normally tied in with
Sensor sizes.

Roy G

wrote in message
ups.com...
I recently purchased a Cannon PowerShot A520 digital camera. I've
gotten pretty good with using many of the features, but I'm still
having a hard time in getting the right "depth" of field shots to look
like the background is blurred and the focus is on the object/person in
front.

Do I have to get a pricey SLR to achieve this effect.

Please advise....

Thanks,

Vonni

If your camera does not allow you to set the aperature, you will never be
able to control depth of field. You want a camera that has aperature
priority exposure control and which can display the view at the taking
aperature on the LCD screen. There aren't many cameras like that anymore.

Another way would be to use the above described camera and consult depth of
field tables. You need to be careful about where you get such tables for
most of them will be computed with a circle of confusion that is appropriate
for 35mm film images. The circle of confusion for digital cameras is almost
certain to be different.

By the way, it isn't especially easy to do this on a "pricey SLR" either
because stopping down to the taking aperature has disappeared in recent
years.
Jim

wrote:
I recently purchased a Cannon PowerShot A520 digital camera. I've
gotten pretty good with using many of the features, but I'm still
having a hard time in getting the right "depth" of field shots to look
like the background is blurred and the focus is on the object/person in
front.

Do I have to get a pricey SLR to achieve this effect.
An SLR makes it easier, but it can be achieved on a P&S to some extent.
If your camera has an "A" setting, use it, and dial in the smallest
number (which means largest aperture) that you can select. If your
camera doesn't have the "A" setting, select a portrait program mode.
Also, it helps to zoom in a bit.
Doing this will make your camera use the least DOF that it is possible
to achieve. If this still doesn't give you much out-of-focus effect,
then you will have to upgrade to a camera with a larger sensor (and
correspondingly longer focal length lens for any particular angle of
view) and/or a lens that has a faster maximum aperture (ie, smaller
number for aperture)

Please advise....

Thanks,

Vonni

wrote in message
ups.com...
I recently purchased a Cannon PowerShot A520 digital camera. I've
gotten pretty good with using many of the features, but I'm still
having a hard time in getting the right "depth" of field shots to look
like the background is blurred and the focus is on the object/person in
front.

Do I have to get a pricey SLR to achieve this effect.

You could get a Canon 350D (look for one on sale before or just after the
400D comes out) and the 50/1.8 (about US$ 70 or so for the lens). Not all
that pricey.

The A520 lens is f/5.5 at the long end, so it's hard. It would be a bit
easier with the A700, even more so with the S3.

Set the camera to "A" (or "Av") mode, select the widest aperture (f/5.5),
and (this is important) zoom out to the longest focal length. Another
important thing is to get as close as possible to your subject. If it's a
portrait, make it a tightly cropped head shot.

The wide aperture, long focal length, and close focusing distance all work
to blur the background.

David J. Littleboy
Tokyo, Japan

writes:
I recently purchased a Cannon PowerShot A520 digital camera. I've
gotten pretty good with using many of the features, but I'm still
having a hard time in getting the right "depth" of field shots to look
like the background is blurred and the focus is on the object/person in
front.

Do I have to get a pricey SLR to achieve this effect.

You can do a pretty good imitation using an image editor.

http://www.gimpguru.org/Tutorials/SimulatedDOF/

On Sun, 10 Sep 2006 08:51:53 +0900, David J. Littleboy wrote:

Set the camera to "A" (or "Av") mode, select the widest aperture (f/5.5),
and (this is important) zoom out to the longest focal length. Another
important thing is to get as close as possible to your subject. If it's a
portrait, make it a tightly cropped head shot.

The wide aperture, long focal length, and close focusing distance all work
to blur the background.

Last night I had the strangest dream . . . In it, a lab
technician (no bubbling beakers) tested myriad cameras and lenses,
furiously taking notes and double checking all entries. Then he
pondered the effect of constraining the exposure settings to some
function of uniform photon capture, shouted "Eureka!" and promptly
set about writing a paper titled "The Long Focal Length Myth".

wrote in message
ups.com...
I recently purchased a Cannon PowerShot A520 digital camera. I've
gotten pretty good with using many of the features, but I'm still
having a hard time in getting the right "depth" of field shots to look
like the background is blurred and the focus is on the object/person in
front.

Do I have to get a pricey SLR to achieve this effect.

Please advise....

Thanks,

Vonni


Some digital cameras feature "portrait" mode, which is usually optimized for
shallow depth of field. If your camera allows you to set the aperture,
select the widest and shoot. You can obtain even shallower DOF by shooting
at telephoto focal lengths, but that may not suit the kind of shot you want
to take.

Ironically, you don't need a "pricey SLR," just one with lenses that can be
manually set. The old Pentax K-1000, as basic as they get, allows this with
ease. Of course you would want to couple the camera with a fast lens, like
the 50// f/1.4 or 50mm f/1.7, and then shoot at wide open or near wide open.

Just one word of caution: shooting wide open typically results in images
that are significantly softer. I had always known this, but only from
seeing the test reports. That point was made to hit home much more when I
saw actual comparison photos of shots taken with the same lens but at
different aperture settings, on Ken Rockwell's web site. He actually
concluded that one's aperture setting made more of a difference in image
sharpness than one's choice of lens brand. So be careful to properly focus
your shot when shooting wide open. You can have a look at the comparison
shots at this link:

http://www.kenrockwell.com/nikon/50-...on/f-stops.htm

Last night I had the strangest dream . . . In it, a lab
technician (no bubbling beakers) tested myriad cameras and lenses,
furiously taking notes and double checking all entries. Then he
pondered the effect of constraining the exposure settings to some
function of uniform photon capture, shouted "Eureka!" and promptly
set about writing a paper titled "The Long Focal Length Myth".

Man, you have some weird dreams, about on par with a lab tech that once
told me she dreamed about be raped by an enlarger. Anyway......
What do you mean by "The Long Focal Length Myth"(all focal lengths in
35mm terms). It is standard practice to do head shots and anything down
to a person's waist with a 80mm or longer. Of course above 200mm you
start to flatten everything out. You can use a 35mm for full length
portrait or groups but anything wider will get you distortion, easy
tests to do. Even a 50mm will give some distortion to head shots. This
is just common knowlege of lens characteristics. Again it is easily
testable.

Tom

tomm42 wrote:

Last night I had the strangest dream . . . In it, a lab
technician (no bubbling beakers) tested myriad cameras and lenses,
furiously taking notes and double checking all entries. Then he
pondered the effect of constraining the exposure settings to some
function of uniform photon capture, shouted "Eureka!" and promptly
set about writing a paper titled "The Long Focal Length Myth".


Man, you have some weird dreams, about on par with a lab tech that once
told me she dreamed about be raped by an enlarger. Anyway......
What do you mean by "The Long Focal Length Myth"(all focal lengths in
35mm terms). It is standard practice to do head shots and anything down
to a person's waist with a 80mm or longer. Of course above 200mm you
start to flatten everything out. You can use a 35mm for full length
portrait or groups but anything wider will get you distortion, easy
tests to do. Even a 50mm will give some distortion to head shots. This
is just common knowlege of lens characteristics. Again it is easily
testable.

Tom

It wasn't a dream. It was from a thread a while back.

The Depth-of-Field Myth and Digital Cameras
http://www.clarkvision.com/photoinfo/dof_myth

But start here first, then read the above article.

Digital Cameras: Does Pixel Size Matter?
Factors in Choosing a Digital Camera
http://www.clarkvision.com/imagedeta...el.size.matter

Roger