Am 10.11.2013 22:02, schrieb clipka:
> Am 10.10.2013 14:52, schrieb Cousin Ricky:
>
>> There is something that puzzles me, which perhaps CLipka could clear
>> up.  For DOF I used an aperture which translates to 7 mm.  For the 19
>> frames I initially jittered the camera within a 3.5 mm radius, but that
>> ended up way blurrier than the DOF run!  I eventually cut the jitter
>> radius by half (and also moved the focal point closer to the surface of
>> the "sphere").  Why does DOF give different results than manually
>> jittering the camera within the same aperture?
>
> That's because...
>
> .... um...
>
> .... damn, I haven't the slightest clue.

There does indeed seem to be a factor of 0.5 buried /somewhere/ in the 
code that I never noticed.

Thus, I have been wrong all the time: The aperture value doesn't give 
the diameter of the camera lens. Instead, it is an entirely artificial 
value that /happens/ to be /twice/ the diameter of the lens.

(That still doesn't mean that jittering the camera position to simulate 
focal blur will get you exactly the same results; one effect that is to 
be considered especially when using strong focal blur is that jittering 
the camera also tilts the image plane, while the jittering used in the 
focal blur code leaves the image plane unchanged. But that shouldn't be 
relevant for the amount of focal blur you used.)

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