Depth of Field....

[GC1]

ok trying to get the best 'blured affects'/Depth of field, from using a 18-55 lens on a canon 400D.....not getting the affect I want any tips or idea's.....

[baz7175]

Shoot on a low F-stop, i.e. 2.8 or however low your lens will go, then focus on something close and the background should go blurred...i.e...


Uglyworld #1006 - Alaaaaaaf!!! (Project BIG - Image 66-365) by www.bazpics.com, on Flickr

[Gemm]

Combination of longest focal length, closest distance to the subject and largest aperture will produce the most blurred background. Also try to isolate the subject from the background.

[RobDickinson]

Yep 3 things determin depth of field.


Focal length - longer = better , so on the 18-55 you need 55mm
Aperture - larger the better , so on the 18-55 you want f5.6 ( widest aperture at 55mm, not very wide!)
Focus distance - closer = better, so have your subject close to you and the background as far away as you can.


Realisticaly IMO buy the 'nifty fifty' for oof/dof shots on the cheap.

[Beardy10]

To get a nice Depth of field you really need something that shoots at F2.8 or less. Nifty fifty as suggested above is definitely the cheapest way to get this.

[Simpo Two]

A 50mm f1.8 will certainly solve your DOF problems for litle money. Other than that, general rule is use aperture priority exposure, crank it as wide as possible and go from there.

[GC1]

Thanks guys for the help...will now start experimenting....

[Original Poster]

I was out in London today, I had a 50mm 1.8 and my mate had the 17-55 kit lens, I got some great DOF shots whereas he couldn't get anywhere near.

As said a 50mm 1.8/1.4/1.2 is really needed.

[RobDickinson]

You can do well with the 17-55 but the 1.8 is nearly 2 stops faster so will be 1/4 the DOF.

[Simpo Two]

Original Poster said:

my mate had the 17-55 kit lens

18-55?

17-55s are usually f2.8!

[Major Bloodnok]

RobDickinson said:

Yep 3 things determin depth of field.


Focal length - longer = better , so on the 18-55 you need 55mm
Aperture - larger the better , so on the 18-55 you want f5.6 ( widest aperture at 55mm, not very wide!)
Focus distance - closer = better, so have your subject close to you and the background as far away as you can.

Size of sensor/film - larger formats have shallower DoF for equivalent focal length and same aperture.

Four things - I'll start again: among the things that determine depth of field are such diverse elements as...

[Original Poster]

Simpo Two said:

18-55?

17-55s are usually f2.8!

My mistake, 18-55!

[Original Poster]

Here's a shot at 1.8...


Strong DoF by chris450D, on Flickr

[RobDickinson]

Major Bloodnok said:

Size of sensor/film - larger formats have shallower DoF for equivalent focal length and same aperture.

Kind of true but not something you can realy change with a twist of a dial..

[GC1]

thats what i'm looking for......

Original Poster said:

Here's a shot at 1.8...


Strong DoF by chris450D, on Flickr

[RobDickinson]

GC1 said:

thats what i'm looking for......

Original Poster said:

Here's a shot at 1.8...


Strong DoF by chris450D, on Flickr

Then buy the 50/1.8!

But remember that pic is pushing it somewhat with a very close subject, f1.8 which usualy isnt at the lenses best etc.

But it is the cheapest way into fast lenses. Stil have my 1.8 even though I have the sigma 50/1.4

[flat-planedCrank]

Nothin beats the 50mm f1.8 for the money

Also a cheap gateway into deciding if you want to spend loads of money on other prime lenses

[RobDickinson]

lol @ 'cheap gateway' , like the first taste of crack...

[XG332]

I love my 50mm 1.4. Great around 2/2.8


Day 70 - The Ultimate Sacrifice - Friday 11th March 2011 by Oliver Meads, on Flickr

[RobDickinson]

mmmm 50/1.4