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Achieving shallow DOF


Malik Sajid

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Ok here is a pretty question that was confusing me since quite a time.

 

how we can achieve shallow DOF with simple dv cams, say XL1, or the one that i am using sony dsr 250? Does DOF depend on lens, or the quality of camera? uh sound stupid.

 

 

i hope u got me.

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Ok here is a pretty question that was confusing me since quite a time.

 

how we can achieve shallow DOF with simple dv cams, say XL1, or the one that i am using sony dsr 250? Does DOF depend on lens, or the quality of camera? uh sound stupid.

 

 

i hope u got me.

 

It's nothing to do with the lens per se, however it is to do with the apeture of the lens. f2.0 will have shallower depth of field than f16. That's true of any lens tho! :)

 

It's also to do with the size of the ccd in the camera. Cameras with a bigger ccd will have a shallower depth of field. It's like with film in a movie camera, the smaller the filmstock, the greater the depth of field.

 

love

 

Freya

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Ok here is a pretty question that was confusing me since quite a time.

 

how we can achieve shallow DOF with simple dv cams, say XL1, or the one that i am using sony dsr 250? Does DOF depend on lens, or the quality of camera? uh sound stupid.

 

 

i hope u got me.

 

The common approach is to put a 35mm DOF adapter on. Basically this uses a 35mm sized ground glass (this can be spinning to reduce the texture), which is in some designed is filmed using the camera's own lens. Of course, the ground glass adds diffusion.

 

There are a number of manufacturers.

 

http://en.wikipedia.org/wiki/Depth-of-field_adapter

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http://en.wikipedia.org/wiki/Depth_of_field

 

http://www.cambridgeincolour.com/tutorials...th-of-field.htm

 

http://www.cs.mtu.edu/~shene/DigiCam/User-...h-of-field.html

 

Depth of field is determined by three things: aperture, focal length, and distance to subject. Wider apertures, longer focal lengths, and closer distances from lens to subject create the shallowest depth of field.

 

The smaller the size of the sensor or film, the shorter the focal length you need to maintain the same field of view. With 1/3" chip cameras you end up with focal lengths so short that wide apertures and close distances often aren't enough to create shallow depth of field.

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And if you shoot at a longer focal length on you zoom so the depth of field becomes less .

 

not actually true.

 

matching the field of view with two different lens lengths and a common stop will yield the exact same depth of field. The longer lens will compress the distance however, making the DOF fall off appear much quicker.

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not actually true.

 

matching the field of view with two different lens lengths and a common stop will yield the exact same depth of field. The longer lens will compress the distance however, making the DOF fall off appear much quicker.

 

And longer lens means a wider lens like 25 or 18 mm???

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arrright

 

 

so how do we control the light say we open the aperture wide open say f2.8 or may be less.

 

Say shooting interview at outdoors, and opening aperture wide may increase the amount of light enterting. We use nets and accessories like that?

 

 

Working with Sony 250p, with lens that can go say from 18 to 125mm, how to play with DOF?

 

Do I really need some fized lens?

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Say shooting interview at outdoors, and opening aperture wide may increase the amount of light enterting. We use nets and accessories like that?

 

 

You use Neutral Density filters on the camera to control the amount of light coming into the lens, so that you can shoot at a desired aperture.

 

 

Working with Sony 250p, with lens that can go say from 18 to 125mm, how to play with DOF?

 

You have all the answers here already. Long lens, wide aperture, close distance to subject; OR use a relay-lens adapter system with 35mm lenses.

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The way to go is to use the camera on full manual mode, set your F stop at 2.0 (as i recall this is max open for the dsr250).

As said before you can use the ND1 or ND2 filter to control your light to stay at this aperture...

 

And also experiment with different focal lengths, if you zoom in nearing the end of the lens your background will look more out of focus (don't go to the very end of your lens, you lose allot of light there).

 

also experiment with the distance of your subject to your lens and distance of your subject in relation to the background.

do some tests this will help you to understand DOF and how to use it.

 

Sander,

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