DoF and sensor size

sirch

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This may be a daft question but I was wondering if a given f-stop gives the same depth of field regardless of sensor size or does the "crop" effect of a smaller sensor change the apparent depth or field?
 
As sensor size increases, the depth of field will decrease for a given aperture (when filling the frame with a subject of the same size and distance). This is because larger sensors require one to get closer to their subject, or to use a longer focal length in order to fill the frame with that subject. This means that one has to use progressively smaller aperture sizes in order to maintain the same depth of field on larger sensors.

Quoted from here... http://www.cambridgeincolour.com/tutorials/digital-camera-sensor-size.htm

Dave
 
Thanks Edward, posts crossed, also a very useful link

On DoF Master, you have to select the camera from a drop-down menu. This changes the Circle of Confusion value (bottom/right corner of the screen) according to format size.

The change in DoF between formats (when the subject is framed the same, from the same distance, with focal length adjusted) is equal to the crop factor. The difference between full-frame and APS-C is about 1.25 stops, ie f/8 on full-frame gives same DoF as f/5.3 on APS-C 1.5x (8/1.5=5.3). If the crop factor was 1.4x, the difference would be exactly one stop.
 
Had to get used to dof when I went FX. Was surprised how much difference there was!
 
Thanks for the replies. Never thought of what it's like on 5x4, biggest I ever used was 120 but that is long time ago.
 
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