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   dware.pc-homebuilt   
   XPost: alt.comp.os.windows-10   
   From: nospam@nospam.invalid   
      
   In article <9LKdncSlBe9dVu_GnZ2dnUU78a_NnZ2d@brightview.co.uk>, NY   
    wrote:   
   >   
   > One other factor to bear in mind: the depth of field varies with lens focal   
   > length, not field of view of the subject.   
      
   actually, it's aperture.   
      
   > This means that if you take a   
   > photo on 120 film and on 35 mm, with appropriate focal lengths of the two   
   > lenses to give the same field of view of the subject in both cases, and use   
   > the same aperture, the DOF will be less on the 120 photo than the 35 mm   
   > photo.   
      
   nope. it will be identical for the same image quality.   
      
   > So if 80 mm gives a certain field of view on 120 and 50 mm gives the   
   > same field of view (ie shows the same extent of the subject) on 50 mm, and   
   > both lenses are at f 4 (and so both will use the same shutter speed for the   
   > same speed of film), the 120 photo will have a shallower DOF. That is why it   
   > is so difficult to get shallow DOF on a compact or phone camera, because the   
   > lens is such a short focal length to suit the very small sensor, that almost   
   > everything is in focus even at a wide aperture (and the lens might have more   
   > artifacts and aberrations than the comparable lens that gives the same field   
   > of view for a 35 mm camera).   
      
   only because the lens on the cellphone can't open wide enough to match   
   the depth of field of the larger sensor camera.   
      
   however, the lens on larger sensor camera will likely be able stop down   
   to match the depth of field of the cellphone camera. some lenses might   
   not, but that's a physical lens limitation.   
      
   --- SoupGate-Win32 v1.05   
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