ND filter or just Decrease aperture and move closer to the Subject to achieve bokeh


torque6

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Jul 7, 2008
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I shot 50mm 1.8 wide open and have always use the ND filter to decreases a couple of stops so I can achieve good bokeh at the same distance. But during a shoot today, I was asked by a fellow clubsnaper to decrease the aperture to maybe F 4.0, move al little closer to the subject and still get very good bokeh and sharp pics. And yeah, it turned out great too.

Any rationale for this?
 

torque6 said:
I shot 50mm 1.8 wide open and have always use the ND filter to decreases a couple of stops so I can achieve good bokeh at the same distance. But during a shoot today, I was asked by a fellow clubsnaper to decrease the aperture to maybe F 4.0, move al little closer to the subject and still get very good bokeh and sharp pics. And yeah, it turned out great too.

Any rationale for this?

Background blur is base on 4 things

1. Focal length
2. Subject distance to camera
3. Aperture
4. Distance from subject to background

Add a Nd only when all 4 factors cannot be changed according to the result you want but your resulting shutter speed exceeds the max shutter speed capable for your camera.
 

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Thanks DD, no wonder ppl used ND filter more for landscapes than portraits.
 

Thanks DD, no wonder ppl used ND filter more for landscapes than portraits.

FYI, "good bokeh" is not the same as "good amount of background blur".
 

Sorry, thanks. Should just be back ground blur.
 

FYI, "good bokeh" is not the same as "good amount of background blur".

Have background blur doesn't definitely will have good bokeh, but no background blur will definitely have no bokeh. :D
 

Add a Nd only when all 4 factors cannot be changed according to the result you want but your resulting shutter speed exceeds the max shutter speed capable for your camera.

to make it a bit clearer for ts sake.
This usually happen when you are shooting in a very bright ambient light condition.
For example; You wanted to shoot in a particular f-stop for getting bokeh in the photo. Your camera is already at maximum shutter speed of 1/4000s. Your shot is overexposed. You have to have to use a ND filter to get a good exposure.
Another situation might happen with you are shooting sporting event and wanted to shoot at a particular shutterspeed to get a nice panning effect at the same time, you wanted a large aperture (small f-number) so that you can "shoot through" fence. In a particular bright condition, this setting will be impossible. Using ND filter will help to lower the amount light entering so that you can still shoot wide open.

I shot 50mm 1.8 wide open and have always use the ND filter to decreases a couple of stops so I can achieve good bokeh at the same distance. But during a shoot today, I was asked by a fellow clubsnaper to decrease the aperture to maybe F 4.0, move al little closer to the subject and still get very good bokeh and sharp pics. And yeah, it turned out great too.

Any rationale for this?

2 things happen when you adjust the aperture;
1. decrease or increase amount of light entering
2. decrease or increase depth of field
 

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There is another situation...

Where large aperture is needed for thin DoF shot, and flash is used to fill in. If shutter speed is higher than max sync speed of camera+flash, some people use an ND to lower the shutter speed.
 

There is another situation...

Where large aperture is needed for thin DoF shot, and flash is used to fill in. If shutter speed is higher than max sync speed of camera+flash, some people use an ND to lower the shutter speed.

thats useful info thanks for sharing