self illum with physical cameras

[tricky]

Just wondered if a self-illuminated effect (using vraymtlwrapper on a self illum standard material) can still be achieved when using a vrayphysical camera. My early tests suggest you can't do this...

[joconnell]

Well the exposure feature of the vray camera mean you'll need to use brighter values than normal - either use a vray light material or use the output levels of your self illuminated materials diffuse to boost it high enough that it comes out the way you like.

[tricky]

Thanks - I'll give it a go.

[tricky]

Mmmm. Not having much luck with Output. How do I set this up? Sorry for being a melon!

[joconnell]

No bother - make a standard mat with 100% self ilumination. Put an output map in the diffuse slot and put your texture map in there or use the vraycolor map to assign a colour. Now use the output amount of the output map to raise the colours level to something that picks up in the physical camera.

[tricky]

Ok - tried that, but now the bits that should be self-illuminated are showing up as dark grey (I used a Vraycolor in the output slot set to white).

Do I need to put this entire material into a vraymtlwrapper?

[tricky]

...well i just tried the vraymaterialwrapper (and told it not to generate gi) and it is still rendering as grey. Maybe I'll try copying the Vraycolor map (set to white) into the standard material's self-illum channel.

(BTW, I have the output amount set to 500 - maybe I'll try 5000))

[joconnell]

What exactly are you trying to do?

[tricky]

I'm just trying to make little glowing 'disks' to appear where my ceiling light fittings are - I want them to be visible, but not generate any GI. They just need to be 100% white, not actually glow.

[joconnell]

Maybe just use a vraylight material and use the vray properties to stop them generating GI?

[tricky]

good idea - will try that!

[DaForce]

Yeah depending on how your vray camera is setup you may need to raise the the MP a fair amount high then before to get it to look white.

But yeah, if you just tell it not to generate or recieve GI then just crank it up so its white, you should be apples

[dlparisi]

What do you have your color mapping set at? It may be reading the pure white as a burned out area and reducing it's intensity (ala Reinhart). Just a thought.

[tricky]

color mapping is gamma with .4545 in the inverse

[rcollett]

I'm currently doing a night scene with a vrayphysical cam, and with my current exposure settings, I've found that the multiplier on my vraylight materials need to be in the 40-55 range. Your settings will be different with different exposure settings, so keep trying.