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01-26-2014, 04:28 PM   #1
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Neutral Density Filters and DoF

Simple question: Do neutral density filters alter the DoF that would normally be associated with a given f-stop? For example if I put a two-stop ND filter on a lens set to f/2, is my DoF like f/2, f/5.6 or something in between?

01-26-2014, 04:32 PM   #2
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Sorry for the brevity, but the filter merely reduces the light reaching the sensor in the same way as a cloud over the sun.

01-26-2014, 04:59 PM   #3
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QuoteOriginally posted by MadMathMind Quote
Neutral Density Filters and DoF
No ND's just knock down light, aperture remains as is, hence dof unchanged.
01-26-2014, 07:35 PM   #4
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ND filters act in a similar manner to the aperture in that you can apply them as needed to reduce the amount of light getting to the sensor. However, the ND filter or any physical filter attached to the lens for that matter acts independently of and in series to the aperture. And as you observed, essentially you can use the filters to control the light and the aperture to control the depth of field.

Since the filters are a light control element, it is good practice to use high quality filters, especially on high quality lenses. A crappy filter up front, does not enhance the capability of an excellent lens.

01-26-2014, 08:47 PM   #5
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Thanks, guys! I recently took some photos with an ND filter at f/2 with a 50mm lens (first time with an ND), but didn't quite give the bokeh I was hoping for. I was worried the ND filter killed my blur, but I guess I was just a bit too far away from my subjects to get the super blur I was seeking.

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