depth of field

[mcarson]

Hey, What's the best way to get a blurry background (shallow depth of field if that's worded right) If i'm thinking right the smaller the f-stop the more the background will be blurred. Also having a background that's far away helps increase it as well. Are there any other techniques? I'm looking at taking some basketball pictures with an f4 lens at 70-85 mm but I haven't been able to get very good results. Thanks!

[Andrask]

AFAIK it's the opposite: the larger the aperture the smaller the DoF.

And yes, the distant background will usually be out of focus unless one uses a very small aperture.

Working closeup with long zooms also decreases the DoF (in macro photography where the distances are very short the very shallow DoF is a major factor to consider).

If there is horizontal movement and you can pan evenly then your moving subject will be in focus and the static background will be blurred.

Of course with digital images, there is always post-shoot processing where it is usually not too difficult to effect the required blur e.g. with Gaussian blur in PS CS2 on a selected background.

[Hellbelly]

I cant believe how long its taking me to get my head around this.

So at say F 2.8, is that called a large aperture and has a small DOF. Say F22, is called a small aperture and has a large DOF.

Is this right? I keep getting the "Large" confused because that actually means small F number.

Hmm, I'm confused again.

HB.

[Marysa]

You've got it
This article gives a simple explanation - hope it helps,
Cheers,
Mary
http://www.dpchallenge.com/tutorial.php?TUTORIAL_ID=1

[swier]

Do not get caught up in techno detail.

Here's what you have said and I don't know if you have realized it.

"So at say F 2.8 [small number], is...a small DOF. Say F22 [large number], is... a large DOF."

now for light and aperture. Small number = smaller amount of light needed... Larger number = larger amount of light. Simply a rule of thumb for general shooting that I live by.

Try to stay away from the confusing truth - small number does mean a bigger opening.

Hope this helps.
Scott.

[sspryte]

hahahah do not worry.....it took me forever and a day to get my head around this one. I was always coming up with photos with EVERYTHING in focus....the cars that I wanted blurred out, the grass, the trees...everything!

[shootem]

Also keep in mind the lens you use has tons to do with dof. A wide angle lens used wide open (12mm @ f2/8) can and will still yield a large dof.... while a telephoto.... say 200mm.... stopped down (f/16) can still yield a narrow dof.... That said, knowing your lens will also help.....

Carolyn

[brenda]

l.o.l... i still cant fathem out all these settings to get correct DOF,all i do is take the same pic with different settings,& when i upload onto the comp the pic that comes out right i write in a little note book the correct settings to use. yer you'll get loads of wasted pics but i found its the easiest way round to trying to figuring out the DOF.

good luck


http://www.chryslerchick.piczo.com

[Rrdjserv]

Some cameras, such as the Canon EOS series, have a DOF preview button. By holding down the button, looking through the view finder and adjusting the aperture (in aperture priority mode) you can see the backgroung in real time before you shoot.