hide object in Iray render but keep the light bouncing of them

drinformation

how can I have objects to bounce the light around but hidden from the camera? I've tried "hide in render" and "opacity", in both cases it was like the object don't exist anymore. please don't add this one to the list of disappointing answers I've got for everything else...

mjc1016

Simple question...can you place a ball on a table and take a picture of it, without it being in the picture, but it's reflection, shadow, etc being shown?

No.

That's how Iray works...it's based on real physics.  There's nothing to be disappointed about.

That said, some or all of it can be done using canvases and light path expressions.  Both functions will suspend/alter 'reality'...

http://www.daz3d.com/forums/discussion/62832/quick-question-about-iray-canvases

http://www.daz3d.com/forums/discussion/58779/iray-canvases-light-path-expressions-and-z-buffer

harrykim

mjc1016 said:

Simple question...can you place a ball on a table and take a picture of it, without it being in the picture, but it's reflection, shadow, etc being shown?

No.

That's how Iray works...it's based on real physics.  There's nothing to be disappointed about.

That said, some or all of it can be done using canvases and light path expressions.  Both functions will suspend/alter 'reality'...

http://www.daz3d.com/forums/discussion/62832/quick-question-about-iray-canvases

http://www.daz3d.com/forums/discussion/58779/iray-canvases-light-path-expressions-and-z-buffer

 

Well this is not the full story !

1. Create a sphere and set opacity to 0.00000000001 

For next steps the sphere must be selected all the time in scenetab

2. Apply the Uber Base Shader ( hold Strg / Ctrl and doubbleklick on the shader and choos "ignore" (screenshot 1)

The shader takes  the opacity value you gave the sphere

3. Apply Uber emission shader ( hold Strg / Ctrl and doubbleklick on the shader and choos again "ignore" ( Screenshot 2)

4. In Surface tab set Cutout Opacity to 0.00000000001 and Emission Luminanz to about 500K (500 thousand)

Make a shortrender ( screenshot 3)

I hope I did not misunderstand the topic ...

 

harrykim

harrykim said:

mjc1016 said:

 

harrykim said:

 

Well this is not the full story !

1. Create a sphere and set opacity to 0.00000000001 

For next steps the sphere must be selected all the time in scenetab

2. Apply the Uber Base Shader ( hold Strg / Ctrl and doubbleklick on the shader and choos "ignore" (screenshot 1)

The shader takes  the opacity value you gave the sphere

3. Apply Uber emission shader ( hold Strg / Ctrl and doubbleklick on the shader and choos again "ignore" ( Screenshot 2)

4. In Surface tab set Cutout Opacity to 0.00000000001 and Emission Luminanz to about 500K (500 thousand)

Make a shortrender ( screenshot 3)

I hope I did not misunderstand the topic ...

 

PS: I have no idea how to control shadow intensity

harrykim said:

 

 

Richard Haseltine

harrykim said:

mjc1016 said:

Simple question...can you place a ball on a table and take a picture of it, without it being in the picture, but it's reflection, shadow, etc being shown?

No.

That's how Iray works...it's based on real physics.  There's nothing to be disappointed about.

That said, some or all of it can be done using canvases and light path expressions.  Both functions will suspend/alter 'reality'...

http://www.daz3d.com/forums/discussion/62832/quick-question-about-iray-canvases

http://www.daz3d.com/forums/discussion/58779/iray-canvases-light-path-expressions-and-z-buffer

 

Well this is not the full story !

1. Create a sphere and set opacity to 0.00000000001 

For next steps the sphere must be selected all the time in scenetab

2. Apply the Uber Base Shader ( hold Strg / Ctrl and doubbleklick on the shader and choos "ignore" (screenshot 1)

The shader takes  the opacity value you gave the sphere

3. Apply Uber emission shader ( hold Strg / Ctrl and doubbleklick on the shader and choos again "ignore" ( Screenshot 2)

4. In Surface tab set Cutout Opacity to 0.00000000001 and Emission Luminanz to about 500K (500 thousand)

Make a shortrender ( screenshot 3)

I hope I did not misunderstand the topic ...

The emissive preset will apply the base shader without having to do so as a separate step, and there's no need to hold down ctrl - that is for ignoring maps in the preset, it has no bearing on values.

harrykim said:

PS: I have no idea how to control shadow intensity

There's no such control in Iray (at least, not in Photoreal mode) - you need to add extra light to fill in shadowed areas if you want them lighter.

mjc1016

Richard Haseltine said:

 

There's no such control in Iray (at least, not in Photoreal mode) - you need to add extra light to fill in shadowed areas if you want them lighter.

Or increase the size of the emitter...very large emitters have 'lighter' softer shadows.

harrykim

oh how embarrassing, thanks and please apologize for my misunderstanding. After posting I asked my self, why not using Pointlight

Well, to late

drinformation

harrykim said:

I hope I did not misunderstand the topic ...

well it wasn't what I wanted but that was another thing I was wondering about, thanks,