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objuan
09-20-2015, 10:43 AM
I have my scene all set up with several lights, the main one being a spot light with a soft shadow map. I like the look of everything, except at one point I pull the camera back quite wide, and the areas on the wall outside of the spot light are too dark. The area inside the spot light is just how I want it, and I do want the soft edge dispersion of the outside of the spot light, I just don't want it to go as dark as it does once we're out of the light.

Is there a way I can add a light (that affects my wall object only) that lightens the shadowed areas, but does not affect the already lite areas?
Or some other means of lightening my wall without changing the area currently in the light?

Thanks

ernpchan
09-20-2015, 11:06 AM
You could try adding lights like directional lights that point to specific areas. You could also try excluding your lights to affect specific geo.

jeric_synergy
09-20-2015, 12:17 PM
There's a WORLD of tricks that could be accomplished w/nodes. One path to examine would be to see if there's essentially a way to have a Light FORCE one Surface on a spot, with unilluminated Surfaces showing a different set of parameters. In this scenario, the bit of the wall that you like stays the same, and the rest of the wall essentially has a different surface. This avoids any gaffer-type issues of spillover that you'll get with Lights, since the change is confined to the Object.

IIRC when Nodes were new there were all sorts of these kinda hacks demo'd, but I haven't seen one lately.

MonroePoteet
09-20-2015, 01:51 PM
In the Light=>Properties panel, there's a "Shadow Color", which defaults to pure black. If you make it a dark grey, it should just lighten the shadows. There's also an "Objects" tab which allows you to exclude objects. Perhaps you could clone your spotlight, cut the intensity in half, set the clone to exclude all objects except the wall, and make the shadows of that one a dark grey. Or some variation on that.

Or, perhaps increase the Ambient Light intensity, and reduce your spotlight intensity by the same amount.

mTp

jeric_synergy
09-20-2015, 02:48 PM
I thought about Ambient, but he specified nothing else was to change, soooooo..... By its nature, Ambient changes everything.

I'm really hoping someone (where's Swampy?) clever can devise a nodal network that would allow what I said above: it would be cool to have lights that could change a Surface from plain to polka-dotted, for instance.

Oh, just thought of another method: IIRC you can get a buffer output that is JUST where a specified Light contributes to the render. Using that and a compositor should make tweaking the outside areas easy. I think the search term would be "special buffers".

pinkmouse
09-20-2015, 03:29 PM
Do it like you would on a real set. Add extra lights to light up the wall as you like it, then just add some odd polys to use as shutters or barn doors to mask off the new lights from the area already lit. No need to get into any compositing or complicated nodal networks, just tried and tested techniques that have worked for 150 odd years in the real world. ;)

spherical
09-20-2015, 08:38 PM
A bunch of techniques come to mind.

Add a bit of Luminosity to the wall surface. Just enough to bring it up out of the deeps.

If it takes too much Luminosity to get to where you like the unlit wall, and the lit area is then blown out, clone the spot and make its intensity negative to pull back the illumination from the spot to where it all homogenizes together.

Separate question: Why are you using shadow maps instead of ray traced shadows?

objuan
09-20-2015, 08:55 PM
Right Spherical, I forgot about anti-lights, I think that is the ticket.
I am using shadow maps over ray tracing because they are soft, but don't cost my sanity in render time/hassle for some radiosity bs.

Pinkmouse, I like your real world mentality, but, screw that schiz, we got NegaLights 5000 up in this biddy!


Thanks fellows!

jeric_synergy
09-20-2015, 10:09 PM
I've been methodically examining all the nodes, and I don't perceive any that allow specific lights to be targeted. But, I'm terrible w/nodes.

spherical
09-20-2015, 10:17 PM
Right Spherical, I forgot about anti-lights, I think that is the ticket.
I am using shadow maps over ray tracing because they are soft, but don't cost my sanity in render time/hassle for some radiosity bs.

Heh. You really need to discover DP Lights. You'll never go back. I left Shadow Maps in the far distant past. Had one scene that had, idunno, 20+ lights with shadow maps. Got tired of waiting for them to be calculated every time I did a test render. And, in most situations, they look crappy compared to ray traced; especially if there are contact shadows, which they don't do at all. DP Lights are independently adjustable in samples to boot. What's not to like?

pinkmouse
09-21-2015, 03:23 AM
Pinkmouse, I like your real world mentality, but, screw that schiz, we got NegaLights 5000 up in this biddy!

I was a real world lighting designer for a long time... :)

Sensei
09-21-2015, 08:32 AM
I thought about Ambient, but he specified nothing else was to change, soooooo..... By its nature, Ambient changes everything.

Download and check Headlight from http://www.trueart.eu
It's Ambient on steroids. Much better look.

Sensei
09-21-2015, 08:35 AM
I'm really hoping someone (where's Swampy?) clever can devise a nodal network that would allow what I said above: it would be cool to have lights that could change a Surface from plain to polka-dotted, for instance.


But that's job of f.e. procedural texture to change property of surface..
There is polka-dotted procedural texture.

jeric_synergy
09-21-2015, 09:06 AM
But that's job of f.e. procedural texture to change property of surface.

"f.e."?

There is polka-dotted procedural texture.
That was just an example.

MonroePoteet
09-21-2015, 01:26 PM
Here's a sort of brute-force approach, which basically uses a "Shadow Caster" object with soft edges to cast a shadow over the area lit by the Spotlight. The ShadowCaster object is parented to the Spotlight and moved down the Z axis (in Light View mode (5)) until it covers the spotlight cone. The ShadowCaster object has an Image with soft edges mapped to its Transparency channel.

The Spotlight is then cloned, and the clone is set as a Point light. The ShadowCaster object is set as "Unseen by Camera", and is Excluded from the Spotlight. The urn object (in this case) is excluded from the Light_Shadows light, as well as any other objects in the original scene that shouldn't be illuminated extra by the Light_Shadows light.

An brightness abberation occurs on the edges of the spotlight shadow if you turn the Intensity of the Light_Shadows light up too much.

mTp

spherical
09-21-2015, 01:38 PM
"f.e."?

"For Example"

spherical
09-21-2015, 01:41 PM
I'm really hoping someone (where's Swampy?) clever can devise a nodal network that would allow what I said above: it would be cool to have lights that could change a Surface from plain to polka-dotted, for instance.

Project an image through the light.

jeric_synergy
09-21-2015, 01:58 PM
Project an image through the light.
:foreheads

JonW
09-24-2015, 12:55 AM
Two lights, the wider light brighter than needed. The second light narrower with a negative number, so it other words it sucks light!

Sometimes a few (negative) fill lights quickly fix some over bright areas.