Issue with Lights during IRAY renders
tsgtkerr
Posts: 20
I am going to try to explain my issue as intelligently as I can, and will likely fail.
I created an in-door scene using a bedroom element from "Dream House" and some Gen3 figures.
With and without added lights, 3DeLight renders work just fine.
With IRAY, it's like the spotlights and distant lights are not seen during the render.
I set all my IRAY render settings to default. I "blinked out" all the walls and ceilings not needed, and the IRAY render behaves like the added lights are not even in the scene and I am running off the organic DOME light from the IRAY environment settings. I tested with DOME ONLY/SCENE ONLY and combo settings.
Am I missing a setting in the lights? or in the render settings?
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Comments
1. Iray will not let light outside the building inside. So you need to hide as many walls/ceilings as you can.
2. If you don't want the environment light, stick with Scene Only.
3. If Scene Only doesn't provide enough light, boost the luminosity of the lights. For spot and point lights the default value is too low.
4. You need a good amount of light, and number of lights, to adequately illuminate a large interior scene.
5. Be sure not to use light sets designed for 3DL. You must either use an Iray light set, or add your own lights after you have changed the renderer choice to Iray.
Thanks for responding Tobor. After investigating your suggestions, I think I may be using 3DL lights instead of IRAY lights. The lights I am using are simply the default lights provided in Studio. Is there an IRAY "on/off" switch for them?
The default lights (i.e, Spot, Point, and Distant Lights) will "switch" to match the render engine. However, light products like the Uber lights and AoA's Advanced Lights are 3Delight only.
Thanks Mike
I just needed a learning curve with interior lighting. All my previous IRAY renders were with TerraDome3 and other outdoor 'rich' lighting. I watched a couple of videos on YouTube and realized I simply had my lum flux setting way too low with my lights.
These are fine, though as I noted it's a good idea to choose the renderer first, then add the lights. This assures that you will then adjust the lights using Iray-centric control settings. Many users unecessarily confuse themselves when they add a light, change the parameters, then switch the renderer. Example: Photometric mode defaults to Off if you add a light under 3DL then switch to Iray. You really want those photometric settings.
Sequence doesn't matter if you stick to one renderer, but doing things with a system helps if you toggle back and forth, even if it's just to experiment.
Another gotcha is that a light in your scene will behave differently in the two render engines. E.g. in 3Delight you control brightness with the Intensity dial, but in Iray you should use Luminous Flux (it won't not work, but you get better control over the light's behaviour). Also, 3Delight doesn't have an equivalent of Iray's Temperature dial, or the Light Geometry controls. And once you get into Iray mesh lights, they behave differently again, with a few different controls.
Something I came across too is that changing from Studio 4.8 Pro to 4.9 Public Beta changes the light intensity. I did this scene in 4.8 and then loaded it into 4.9 and it was dark at the settings used. In 4.8 the Luminous Flux for the Key Light is 10, in 4.9 I had to turn it up to 55500 to get the same amount of light, at 10 it was too dark. There are another two lights set at 5 in 4.8 which I had to increase to 1500 before they would show any light. No other settings needed changing, I will need to change her skin though as she has got quite a tan in 4.9 :)
This appears to have been a change in the way the distant light is calculated. In 4.8, the light is calculated as lumens incident per centimeter square; in 4.9, they inexplicably changed it per meter square, several orders of magnitude difference. I don't use distant lights much, but when this change was first discovered some months ago, people reported that the apparent brightness was corrected by multiplying the old value by 10000 -- that's the difference between cm and m.
Iray's default unit of measure is the meter, whereas it's the centimeter in D|S. I suspect that the change in distant light was unintentional; but if intentional, unwarranted. At least the light is still based on incident illumination (as the value of the sun would be) rather than radiant power measured at the source.
There may be changes in some of the other light factors, too, but not to this degree. Other differences may have to do with changes slipstreamed into the Iray engine.
iRay renders way too dark, and much too slow--with most Daz3d enviornments, which do not work as advertised and are unresponsive to changes in the lighting setup, including external architecture. If you can't control the lighting, iRay is absolutely a lost cause, and I wouldn't go buying new content before this problem is fixed. It's already more than a $1000 3D program for me, but disappointing.
In September, I purchased Poser 11 Pro. I wouldn't get into the business of comparing 3D programs, since people are doing that all over the web. I would say Poser is a lot easier to use, with a faster work flow. Daz3d is really nice in a lot of ways, especially the artwork in figures and other content, but it's frustrating that the same old problems persist for months or years, and kluges are frequently required to carry-out basic functions like lighting the scene.
Using HDRs with enclosed spaces will be dark and slow (and have a lot of noise). If you rendering in an enclosure you ned local lights (points, spit, or emissive surfaces) and to adjust the Tone Mapping in Render Settings. Foe environments with skydomes, remove the dome.
I am struggling with an indoor set ( post apocalyptic living room )
I have it set to scene only in render settings, and the light lumens at 555000.0 and its like it doesnt exist, iray shows nothing.
I am getting a very tiny amount of light through a window and nothing seems to be adding any light for iray mode.
No matter what lights I try, distant, spot, head, emissive surfaces its like they do not put out any light or affect the scene in the slightest.