Emissive shader (a TV screen), shows all brown.

Robinson

I'm wanting to show a TV screen with a cartoon image on it.  When I use the default uber shader with a diffuse map it all looks fine, i.e. as the image on the right shows.  When I apply the emissive shader and set the base map to my cartoon image however, I get the result on the left ("brown").  

 

What am I doing wrong with the emissive shader?

 

 

 

nonesuch00

I think that is because the light being emitted overwhelms the 2D image which only has reflection properties which are overwhelmed by the emiision property.

Try turning off emission and place a small rectangle behind the TV and make it emit white light about 100W at 6500K (experiment with light wattage from 5W to ...?), then make the picture surface opaque so that some of the light gets through the screen and makes it look like it is lit. I think to do that you will need to make a cutout opacity map the same size & shape as the TV picture and place it in the cutout opacity map.

That's me best estimate how to go about solving your problem easiest, someone with more experience may correct my or suggest an easier method.

fixmypcmike

I haven't done it in a while, but I think you need to put the image in the Emissive Color channel.

Robinson

This is so weird.  I looked for a paramter like that but couldn't fine one.  However this time I put the map into the emissive channel on the base shader and *then* applied the emissive shader.  The parameter was still there, so I set it to the map and now it works.

 

Thanks.

nonesuch00

Oh, that works better and is much easier than my guess. Thanks.

Fishtales

Putting the .jpg in the emission colour was how I made this panel light up.

Click on image for full size.