"Bill Pragnell" <bil### [at] hotmailcom> wrote:
> "Trevor G Quayle" <Tin### [at] hotmailcom> wrote:

> > No wrapping and rotating at the same time is fine.  I still would always
> > recommend Lat/Long format over angular.
>
> Any particular reason? Does this projection preserve more information? I expect
> I can still do the blending in HDRSHop... ?
>

No particular reason other than I find them easier to work with and view.
Reasons I like lat/long:

-Easy to open and view and understand the scene.  Any rotation from horizontal
is also usually easy to see and correct.  Viewing and angular map, I find it
very difficult to understand what the overall scene looks like.

-megaPOV may have the angular map-type, but not all programs do and it is very
simple to wrap the lat/long to a sphere.

- I have an extensive lightdome macro that I have developed for POV.  It is much
easier to parse and analyze the lat/long format


I don't know wheteher they preserve the information better or not for certain,
but I do suspect that they make more efficient and uniform storing of the
environment data.  They actually do contain more information than necessary, as
they get spread apart towards the poles.  A true equal representation would be
cos shaped progrssing from a width of 1 circumference at the equator to 0 at
the poles.  Angular maps only occupy a circular portion of the square image and
not all of this is efficiently used, as one progresses outward from the center
(ie angle from viewing line increases), the number of pixels (circumference)
increases linearly, whereas, to be equal, it should progress sin shaped.  For
angles from 0 to 90, there are less pixels than ideal by up to 50%, from 90 to
180, there are more pixels than ideal, meaning less efficient storing of the
data.

-tgq

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