Correct. Thus a direction of theta = 45 deg, phi = 90 deg, is the same
direction either above or below the surface. The theta,phi coordinate
system does not change depending on where you are. If you're in the air
(depth flagged as -1) looking down in a given (theta,phi) direction,
then you're seeing the total upwelling radiance (in air) in that
direction. If you're in the water looking in the same downward
direction, you're seeing the upwelling (underwater) radiance in that
direction.

Refraction at the surface is accounted for by the fact that radiance
from one quad in the air maps into one (or more) different quads underwater.

Curt

cindyzju wrote:

>
> So in the full radiance output file, if the radiance is just below
> the water surface (like say 0), the angle in that radiance table
> (theda and phi) should be referring to under water angle while the
> angle for the above surface (like say -1) radiance should be in the
> air. Am I right?
>
> Thanks
> --- In HydroLightUsers@yahoogroups.com
> <mailto:HydroLightUsers%40yahoogroups.com>, Curtis Mobley
> <curtis.mobley@...> wrote:
> >
> > The directions in H are defined by the partitioning of all
> directions
> > into "quads", as shown in Fig 2 of the Users Guide, and as
> described in
> > section 2.4 of the Users Guide. These directions/quads are the
> same
> > above and below the sea surface. Thus, for example, if the sun is
> in a
> > particular quad above the surface, its refracted beam will be in a
> > different quad below the surface (for a level surface). Let me
> know if
> > this doesn't answer your question.
> >
> > Curt
> >
> > cindyzju wrote:
> >
> > >
> > > If I use the full radiance output setting, the angle I get is
> below
> > > the water or in the air or depends on the which depth I am
> gettting
> > > from?
> > >
> > > thanks
> > >
> > >
> >
> >
> > --
> > -----------------------------------
> > Curtis D. Mobley, Ph.D.
> > Vice President and Senior Scientist
> > Sequoia Scientific, Inc.
> > 2700 Richards Road, Suite 107
> > Bellevue, WA 98005
> > voice: 425-641-0944 ext 109
> > fax: 425-643-0595
> > email: curtis.mobley@...
> > WWW: www.sequoiasci.com
> > personal: www.curtismobley.com
> > -----------------------------------
> >
>
>


--
-----------------------------------
Curtis D. Mobley, Ph.D.
Vice President and Senior Scientist
Sequoia Scientific, Inc.
2700 Richards Road, Suite 107
Bellevue, WA 98005
voice: 425-641-0944 ext 109
fax: 425-643-0595
email: curtis.mobley@...
WWW: www.sequoiasci.com
personal: www.curtismobley.com
-----------------------------------