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fredfx
08-20-2015, 01:39 PM
Hi Community:

I need to render a reflection of an item descending from the top of the frame.
I have the scene lit with an HDRI sphere.

Normally in a scene without the sphere, I'd put a card on the groundplane, set the reflectivity to 100, lose all the other items in the scene so that I'd just
have the inverted image over black.
Since I'm using the sphere to light the scene, I want to retain the lighting on the descending object, but I also get the reflection of the HDR
sphere in the card on the groundplane. I really just want the descending item. I think you can see what the issue is here.

There has to be an elegant way of doing this. Anyone have an idea or suggestion?
My pea brain is about to explode.

best,

Fred

madno
08-26-2015, 03:56 PM
Hi,

just saw your post. Here is my idea (but I am not sure if I understood the question right).

You can put an hdr on a sphere and use some nodal to control the attributes of the hdr indepentently.
I was able to set up something that let me control:
- reflection, saturation, direct intensity and GI intensity

The nodes:
129499

What they do:
129503 129502 129501 129505
(GI-saturation is not relevant in this example because the hdr is anyway just gray)

This might not work in all situations but helps me sometimes.

prometheus
08-27-2015, 01:38 PM
perhaps this..if you skip hdr on a sphere and put the hdr on the textured environment instead?

go to surface editor, select all surfaces, go to the environment tab and for reflection options, use ray tracing and spherical map, that should kill off hdr map in reflection if you have that setup in textured environment, but it will still raytrace reflections that is caused by other items.
Edited.

to kill the hdr background in the rendered image a set in textured environment..and only use it for lighting, use background color in the compositing tab.