I searched for how to turn off a reflection in lights, and found a post, but I didn’t understand the answer.
As you can see in this picture, Visible in Primary is False, so I don’t understand why a reflection would show up.
Second question - How do I create a visible light of a certain color.
If I create a light, and change it’s color, the objects that are lit up use the color specified. However, if I check Visible in Primary Ray, the light itself is not the color I selected. Oddly, the reflection is the correct color, but not the light itself.
What is the trick to create a Red or Blue light (bulb) ?
Thank you
As you can see in this picture, Visible in Primary is False, so I don’t understand why a reflection would show up.
If the light is only invisible for primary rays, that is, connections from camera to the light itself, then the light would still be visible in all other paths like reflections or transmissions which are not primary rays. Otherwise there would be no illumination from that light inside the scene.
If I create a light, and change it’s color, the objects that are lit up use the color specified. However, if I check Visible in Primary Ray, the light itself is not the color I selected. Oddly, the reflection is the correct color, but not the light itself.
That’s because the light is brighter than white and not a primary color. You cannot represent that inside a low dynamic range image.
That the color of the light is visible inside reflections is because the reflections are a lot darker due to the material absorbing light.
You should be able to see that the light is colored itself if you bring its intensity or better the exposure or brightness of the tone-mapper far down.
To answer you question very specifically on a red or blue light bulb, you can take a simple sphere light and make it pure red, or pure blue with primary ray visible ON. As mentioned above, don’t think of the light icon as a physical bulb though. Only if I use a pure full RGB red (255,0,0) do I get a red light. Anything less intense than that because of HDR and light intensity will appear mostly white. If you want to “see a red light” you can just put a self illuminating red sphere in there.
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Thank you for the reply. Can you tell me how I create a self illuminating sphere?
That did work if I set the color to 100% red.
Thanks
To create a self illuminating sphere, it is just a sphere with a self illuminating material applied. You can make any material self illuminating by going down to that section and turning it on and setting the power and temperature.
We also have some great presets of “light” materials in the material library.
Thank you.
Maybe you know this. I have seen the Emissive materials, but I don’t know how to change the color of them. Is that possible?
Thanks
If you scroll down to the emissive section of the material you will see power and color temperature and an RGB color picker. You can change the color there. If you want to use color temperature, you have to first hit the check box to switch to that mode. Making the temp very low, say 3000 will make it red.
OK, thanks. I guess I never scrolled down.
