Gangmax Blog

The DOF(Depth of field) formula

The DOF(Depth of field) formula is:

  • DOF = depth of field

  • u = distance to subject

  • N = f-Number

  • c = circle of confusion

  • f = focal length

The formula comes from Google result.

The method how to write mathematical expressions in markdown format(GitHub style) comes from here.

The “c” values of different camera can be found from the web page here which provides an online DoF calculator implementation. Here are some examples:

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<option value="0.005">Nikon Coolpix S8000</option>
<option value="0.005">Nikon Coolpix S8200</option>
<option value="0.005">Nikon Coolpix S8100</option>
<option value="0.005">Nikon Coolpix S9100</option>
<option value="0.005">Nikon Coolpix S9300</option>
<option value="0.011">Nikon 1 J1</option>
<option value="0.011">Nikon 1 V1</option>
<option value="0.020">Nikon D1H</option>
<option value="0.020">Nikon D1X</option>
<option value="0.020">Nikon D2H</option>
<option value="0.020">Nikon D2Hs</option>
<option value="0.020">Nikon D2X</option>
<option value="0.020">Nikon D2Xs</option>
<option value="0.030">Nikon D3</option>
<option value="0.030">Nikon D3x</option>
<option value="0.030">Nikon D3s</option>
<option value="0.030">Nikon D4</option>
<option value="0.020">Nikon D40</option>
<option value="0.020">Nikon D40x</option>
<option value="0.020">Nikon D50</option>
<option value="0.020">Nikon D60</option>
<option value="0.020">Nikon D70</option>
<option value="0.020">Nikon D70s</option>
<option value="0.020">Nikon D80</option>
<option value="0.020">Nikon D90</option>
<option value="0.020">Nikon D100</option>
<option value="0.020">Nikon D200</option>
<option value="0.020">Nikon D300</option>
<option value="0.020">Nikon D300S</option>
<option value="0.030">Nikon D700</option>
<option value="0.030">Nikon D800</option>
<option value="0.030">Nikon D800E</option>
<option value="0.020">Nikon D3000</option>
<option value="0.020">Nikon D3100</option>
<option value="0.020">Nikon D3200</option>
<option value="0.020">Nikon D5000</option>
<option value="0.020">Nikon D5100</option>
<option value="0.020">Nikon D7000</option>

From the list you can see that, for a “full frame(35mm)” cemara the “c” value is “0.030” while for a “APS-C frame” camera the “c” value is “0.020”. These two values cover most of the user scenarios.

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