I think that it should be more like this:
camera	{
	location 0 
	sky SurfaceDirection 
	look_at vaxis_rotate( ?? , SurfaceDirection ,Degrees )
	angle 40 
	translate Surface*1.002
	}

The SurfaceDirection vector determines where on the sphere.
The Surface vector is the distance at that spot.
Degrees is how much to rotate around the SurfaceDirection vector.

Those Three I already have. Its those two question marks in
vaxis_rotate( ?? , SurfaceDirection ,Degrees ). They represent
a point on the plane at Surface distance from the center that is
tangent to the sphere.
The SurfaceDirection vector is the normal to a plane tangent to
the sphere. I need to find a point on that plane so I can point
look_at in the proper direction.

Does that help? Maybe I should try a different approach, maybe not.

Mr. Art
ingo wrote:
> 
> Is this what you're looking for?
> 
> #declare Radius= SphereRadius;
> #declare Offset= WhatYouWant;
> 
> camera {
>     location <0,Radius+Offset,0>
>     look_at <0,Radius+Offset,Radius+Offset>
>     rotate <random, random, random>
> }
> 
> ingo
> --
> Met dank aan de muze met het glazen oog.
> Arthur Flint heeft geschreven in bericht <379A1910.98B51D61@gci.net>...
> >I have been working with placing a camera on the surface of a sphere
> >on a random position. I would like the camera to be aligned so that
> >the the surface is "down". I guess that "up" would be the vector to
> >rotate
> >around to view the surface.
> >Assuming a vector of SurfaceDirection as "up", what are the prameters
> >for the camera?
> >--
> >Advanced means constantly wondering where reality gets its processing
> >power.

-- 
Advanced means constantly wondering where reality gets its processing
power.

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