Hello,

I want to get some opinions on my following assumption:

When I render with IBL light or env sphere, must the camera be at position 0?

The way the HDRIs are recorded, all the light is collected by a sphere in the center of the world, so I assume the answer is yes. On the other hand, the sphere will have been some distance away from the ground, so is it x=0, z=0, y=something instead?

With the environment sphere, because it takes over the IBL lighting, would the camera position be arbitrary then, as long as the sphere is loaded at the same location as the camera?

I tested this and at least it does not look wrong. Still open to find out would be to get the correct value of y=something.

Best regards,

   Michael

Michael

I appreciate that English isn't your first language but it's not clear what your question is.

The use of IBL or an Environment Sphere has nothing to do with camera position.

Hello cspear,

you have answered my question already. It was:  What is the correct camera position when working with IBL or env sphere?

My assumption was that the camera position is somehow restricted (because in some extreme case, you could move the camera outside of the env sphere).

Best regards,

   Michael

Quote - My assumption was that the camera position is somehow restricted (because in some extreme case, you could move the camera outside of the env sphere).

Well, you can move the camera outside the env sphere - if you're using bagginsbill's free one, this is just beyond 250 Metres from the centre (so the env sphere has a diameter of around 500M). I can't think of any situation where I'd want to do this, but the answer is simple: make the env sphere bigger!

If you scale the env sphere 500% you can move the camera 1Km away from the centre if you wish.

I don't have much practical experience with an environment sphere, but just thinking  about it, it seems to me that the answer to your question must be "yes".

You camera has an angle of view, and this, together with its position and orientation, determines its field of view (what it sees). As the camera leaves the center of the sphere and approaches its surface, it must of necessity see a smaller area of the spheres surface. How much latitude you have before the effect of moving the camera becomes obvious will depend on the size of the sphere. The bigger the sphere, the more you can move the camera before the effect becomes obvious.

With IBL light, but without the environment sphere, it will depend on the size on the sphere that Poser uses. The size of that sphere might be infinite, or so large that it can be treated as infinite for most practical purposes. I would expect that it is so, but can't be certain.

Not quite correct answers.
As far as I remember, the sfere can be made bigger but Poser does not see infinite.
It stops seeing obj's at a certain distance, but I do not remember what that distance is.
Anyway, why would you go that far away anyway?

The sfere is a very usefull tool, and I hope BB steps in on this.

...and I as I recall bagginsbill posted a special thread about actually rotating the env. sphere on the Y axis to adjust the light position.

But wasn't that in relation to IDL, not IBL as the OP is referring.  In such a case, self illumination of the envsphere is taken into account in the final, overall scenelighting.