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So, imma start this thread here for lighting discussion and keep it going, i'm not a pro or anything, but whatever i can think of, i can usually recreate it pretty well and would love to share ideas. iRay lighting is freaking awesome, once you figure it out.
For starters, you tube some stuff. Daz3d iRay lighting techniques // volume lighting in daz3d // dust and fog in daz3d etc...
This one was pretty good for the tech stuff with dust and lighting and helping create god rays.
[Tutorial] Creating Dust And Atmosphere in IrayWhen i render in iray, i don't use any lights. I create emissive objects, usually light bulbs, neon lights etc... and set those settings. It differs from scene to scene. I'll post some examples i have done already, and some new ones to show different ideas.
Emissive light from bow, with bright background image.
Yes, in iRay, turn off the headlamp, and go to render settings environment tab and chose scene only lighting. Then you get to really start create true light effects.
Small Scale example of single emissive sphere with scene and headlamp off. (Remember to create a new camera // don't use the built in view cameras, you can't really disable headlamp from them)
Then you can create all sorts of types of light. I've done a distant sphere at like 100 meters in diameter at 100000s of units away, and cranked the light way up to create true sun like feeling, here are few of those
In the billy the kid one below, created a distant mountain range, and placed the sphere behind it, played with the size and lighting to get this... (PRE POST WORK)
And after a bit of screen overlay to get the old timey look...
The beach is a bit of a trick, place the sphere below the horizon, line it up with the sun of the background image, send it way back, like way way way back, and keep playing with the intensity and temperature of the light until it is just right
start small, like the first one and play with it. If you're using a background image like above with sun in it, once you line up the object, set it's opacity to almost 0, like 0.0001 ... it still emits the light the same, but doesn't create that hard circle, and give the effect that it came from the image of the sun.
Using this method, once the sphere is in the right place, and your using a backdrop image, make the sphere a child of the camera, so it doesn't move out of place, since the background image doesn't rotate either. If your using a sky dome like in the billy the kid above, then don't set it as a child.
In the iray shader library, there is an emissive shader for getting started, select the material of the object you want to become emissive and apply that shader, or make the emissive property color anything but black. That will expose the rest of the dials.
You can, of course, use the default and built in spot lights and point lights and distant lights, but you don't get a good feel from them. I love the sphere light since it softens the shadows for a more realistic look.
Materials on Objects already in scenes can be converted to emissive lighting as well, below the sabre and some of the edges of the walls are emissive, though that scene was precanned that way.
In the sith render above, i played with the bloom effect and threshold to get just the right amount of glow.
Mix and match stuff as well, cold light in front, warm light behind in this one, I used small emissive spheres for both, pretty close to the character i created here.
Tying it all together, single emissive object in the lamp, dust and atmosphere configure to help diffuse the light, didn't turn out the way i wanted here, but the effects worked as they should. no builtin lighting.
Same character on black matte floor with single iray emissive lighting and mild atmosphere cube to diffuse the lighting ...
Just thought i would throw some stuff out there, and open a discussion, and hopefully share what know, and learn some new stuff from others too.
Let me start by saying that turning it to 'scene only' makes zero difference to me.
I have this enclosed, indoor space. If I render with zero lights, the whole scene is uniformly lit somehow. Yes, the headlamp is off. I can add very powerful spotlights, but they are barely visible because the mysterious light that is always there just overpowers it. I want my room to be pitch black with the exception of my spotlights.
Where is this mystery light coming from? How do I get it to go away so I can see only MY lights?
Your environment probably contains mesh lights. You’ll need to find them and turn them off to totally control your lighting.
Mesh lights are not effected by environment in render settings. What environment are you using? Look for lamps, overhead lights, wall sconces, stuff like that.
Once you find those mesh lights, change their emission color to black and they will no longer illuminate.
@ Aftyr Byrn
You have some very nice images there, well done. But a slight correction. It isn't IRay lights that are awesome, it is the render engine and how it uses light because it is an unbiased render engine. IRay is a decent render engine and someone with your skills can make some very nice art with it.
In your second last image with the three guys and the single emissive object (lamp) something is wrong, there must be another light source because the back of the nearest character is lit, as is the front of the guy he is talking to even though they would occlude the light. Not a complaint though, just an observation 😉@baf-mcnab, yeah probably was an additional light, i was quoting from memory, i can't find that save in my folders. It was bugging me and i went with the single character when i finally submitted that one. looking at it now, i think there was a 'moon' somewhere to get the cool lights in the distance.
And true, it's the iRay Rendering engine.
@Aftyr Byrn
NP, I ought to explain more about how the computer draws a 2D image from a 3D scene.
It used to be that there were two basic methods that a render engine could use. Biased and Unbiased. Biased sends rays FROM the camera plane into the scene, for arguments sake imagine one ray per pixel. Each ray will do one of several things. It will not hit anything and thus that pixel will assume the background colour (or black), it will hit something and then it can do one of several other things, it can bounce off that thing, it can be absorbed, it can pass through and carry on straight, or it can pass through but get refracted (glass or water etc) These rays will carry on their merry way until they either hit a light source or vanish in to the virtual ether. Only rays that hit a light source will yield good information for the final render. As you can imagine there are lots of wasted calculations using this method AND this is not how it happens in real life. 3Delight uses this method essentially.
Unbiased works more like real life in that the rays are sent FROM the light source. Some of these will find the scene and a fewer portion of those will bounce up to the camera plane. Again, there are a lot of wasted cycles, especially if you used a sphere as a light source because rays would go from that sphere in ALL DIRECTIONS. and only a few would find the scene.
BUT then the clever bods came up with a variation called bi-direction ray tracing. This uses the best of both methods to figure out which are the best paths for the rays to travel. The final image is still created using information from the rays that are sent FROM the light source(s)
The IRay that we get to use in Daz studio is a 'cut down version' but it still uses Unbiased rendering. So now you know why I pointed out the light in that one image didn't point to only the one source.
3Delight can use 'tricks' to fake some real world things such as bounced lights BUT Biased rendering cannot bounce lights per se, Unbiased can.
As an aside you may have heard about the new RTX 2k graphics cards from nVidia that promise 'real time ray tracing'. These are aimed primarily at the games world. Games have in the past used another kind of rendering that I used to know as scanline rendering (and/or rasterization) In games a lot of information is baked into the textures of the objects that appear on screen. This is why you can have games that draw at more than 100 frames per second. But until now they have not used ray tracing. This new card will eventually change that and games will look better than ever but for an application to use the new cards, the code will have to be re-written . Sooner or later that may also happen for IRay. Then renders will be instant 😉
Apologies if you knew some or all of this, but I thought it might be useful for any new users of Daz studio, especially if they begin to wonder why a lot of Gen 8 figures do not come with 3Delight mats 🙂Thanks @afterbyrn and @baf-mcnab...
Lots of good info.Question... Are emission lights easier on ones system than the regular lighting? Or would they bog it down?
As in, Using HDRI lighting seems to be quicker/easier on my system than the regular lights. I'm talking major light source, not an emissive window or sword.Good question. We used to speak about directional lighting being the best, which was why I went into such an in depth explanation. HDRI's are firing rays into the scene from all around, that equals plenty of info that can be used for the final image and of course more closely mimics real life. Ergo HDRI's do tend to be a good quick and easy way to add 'realistic' lighting but they are mostly only good for outdoor scenes. For indoors you can use a plane out of view of the camera but with an emissive shader to light the scene, I have often done this for room scenes instead of using one of the more conventional lights such as a spot. I would suggest that emissive are no easier or harder on the system, in that other factors will add more 'strain' onto things such as how many polys you have in the scene and especially shiny or reflective materials. I don't use emissive lights that much in Daz so don't have a lot of experience sorry. (I DO use them in Blender :))
Maybe @Aftyr Byrn has a lot more experience than me and can answer that question better.
OK, cool. Thanks
@aftyrbyrn, you're next, Mr emissive 😉@drgnmztr Emissive, easier? I don't know about that, it's a matter of preference. I built my system to play games and render, and in benchmarks, I'm generally in the top 2% in it's class. 1080TI Extreme 11 GB, over clocked, 4.8GHZ i8700k and pure SSDs for all my graphics and game storage. Before the 1080TI, i would have waited hours upon hours to get a good render, now it's just minutes. (from a NVIDIA 970 STRIX and i4790k)
The reason i use emissive lighting is because i like the realistic feel and logical configuration. I had so many problems with spots, points not giving off enough or the right light, shadows just looking fake and too crisp with built in lights (in some cases, i know you want that). But with the 'emissive' (i'm not even sure it's the right term), i get very natural feeling scenes. Soft shadows, good bounces and all.
I never got into tweaking HDRI other than what was canned in some of the packages, and yeah, it did OK, but if i wanted a forest scene, with fog, and light coming through the trees, at from a central point, it wouldn't have worked. Once i figured out how to use different objects for lighting, mesh objects, enabling light emission, i was like, yeah, that's the ticket. Remember my Christmas banner render from last year, that was all point lights, but now i could have done that completely differently, as a matter a fact, i think i'm going to locate that and render one with the point lights, and one with emission on the bulbs and see what kind of difference it makes.
Anyway, you'll have to play around with each type, and see which you prefer, beauty is in the eye of the beholder, and i'm biased. Not sure what you have on your side for a rig.
As for more experience, it's all street smarts, and doing this since poser came out on floppy at babbages in the mall almost 25 years ago. (sorta the same with my job, but that's another story #novalidcerts #seniorengineer #lol)
@aftyrbyrn yeah um, well, um... Lets just say that an EVGA GeForce GTX 1060 6GB card is on deck for purchase. It'll bump my render time exponentially.
wait for the 2080s to come out before you buy if you can, prices should come down on the 1080s....
@ Aftyr Byrn
Good shout on the deals, and here is a post with more good advice for anyone thinking about upgrading their cards
https://zonegfx.com/forums/topic/cheaper-gpu-deals-popping-up/
BTW Aftyr Byrn, I have been at it longer than you if all you have is a mere 25 years 😛
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