"Bill Pragnell" <bil### [at] hotmailcom> wrote:
> "Edouard" <pov### [at] edouardinfo> wrote:
> > > - make sure there is minimal movement of background objects (ie, cars
> > > driving, people walking, even fast moving clouds) as this can be quite
> > > evident and cause visual errors in assembling the HDR.
> >
> > Clouds in particular move ore than you think they do...
>
> I am well versed in this regard, I've been stitching regular rectilinear
> panoramics centred on the horizon for some years now. Clouds are not as bad as
> foreground parallax errors - I don't have a suitable tripod, so I try to
> minimise parallax by rotating myself around the camera lens!
>
> People moving can also be a problem, but as long as they stay out of overlap
> regions it can work out (at least for regular panoramas). I took one where my
> friend in the foreground appears twice - she skiied on while I was taking the
> shots.
>
> Thanks for the tips, both.
>
> Bill

With HDRI this is even more pronounced as you are not just dealing with overlap
parallax, but also assembly of several exposures.  While moving objects for
panorama stitching can be hidden or minimized and don't really cause huge
problems other than little ghosting, they can cause ugly noticeable errors in
the calculation and assembly of HDRIs from multiple exposures.  The HDRI
assembler is basically taking the pixel value from the same area for each
exposure and creating a true dynamic value, as sudden change in one exposure
due to a moving object can cause chaos for it.

-tgq

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