Indigo Renderer Forum

Hi, I'm trying to use the parameters "base_emission" and "emission" to simulate a TV set.

Which are the "physical correct values" for the spectrum?

I've used empirical values, but I prefer to use "phisical values".

Same question to simulate a neon tube (by emissive material), my next test. (e.g. a 32 watt linear neon tube)

Thank you

Delle

P.S. here is the "screen material":

<!-- Material : "_Mtl31 (5)" -->
<material>
<name>Material_7</name>
<diffuse>
<texture>
<!-- TextureMap[0] : "Mappa emissione" -->
<uv_set>default</uv_set>
<path>.\__Test Indigo Emission\CLP102_EMIS_RGB.bmp</path>
<exponent>2.2</exponent>
<b>1</b>
</texture>
<albedo>
<constant>
<rgb>
<rgb>0.572549 0.572549 0.572549</rgb>
<gamma>2.2</gamma>
</rgb>
</constant>
</albedo>
<base_emission>
<constant>
<rgb>
<rgb>2705.882490 2705.882490 2705.882490</rgb>
<gamma>2.2</gamma>
</rgb>
</constant>
</base_emission>
<emission>
<texture>
<texture_index>0</texture_index>
</texture>
</emission>
</diffuse>
</material>

The tv on the left should be more inclined towards the wall...

For fluorescent lamps some spectrum charts are available on the net and manufacturer documentations, just gogole them.
For tv image, I don't know, spectrum values may depend on the displaying image.

delle, please use the Code tag in post for materials, actually reading them is a bit of a nightmare, it's so better with identation...

You should put a reference surface in your scene, the floor doesn't help for evaluation, I would use 50% gray diffuse instead. Maybe put a sphere in front of them, of the same material. For now I have the feeling that they are weak, but if you use reinhard tonemapping, my evaluation could be biased by a low ior, dark floor

Put a physical light nearby so you have a referential for comparison, or render it separately, given that both images would be using the same linear or camera tm settings, and environment material.

The overall picture is nice, what is the problem?

Calibration !? delle is seeking for correct tv emission v... alues

Calibration !? delle is seeking for correct tv emission v... alues

Exactly, I've used Povray for years, I don't want to simulate reality (like Povray does) I want to render a scene closest to reality as possible I can.

Delle

Use your eyes then...

If delle wants to work with spectrum, it would mean that he's hardcore enough to not be satisfied to work with his eyes only.
I quite understand him about fluo tubes, and know that real reproducing tv is problematic.
However I found this which contains a spectrum chart of phosphore light of an early tv set, and it seems that this was not so complex, modern screens are probably better and easier to render in Indigo than I expected.

So he want's to pick rgb values of images, which means which they mean and translate it to phosphor light, all the best for him then... meanwhile he might as well model those dots and separate the colors... just for the sake of being real