Setting Decay value for lights in DS 4.10 Pro
magog_a4eb71ab
Posts: 769
There's suppose to be a setting for this, and I've seen it shown as "Decay" in an older version of Daz, but I'll be damned if I can find it in 4.10.123 Pro. Has it been renamed to something else, like "Ray Length"? In the past, others had issues with lights not appearing to render as intended, and one of the causes was the Decay value was set too high. I also recall reading in an older post that if you're using Iray rendering, you want to adjust Luminous Flux for intensity instead of using Intensity. Anyway, here's the list of the tools I have under Spotlight(excluding the x,y,z parameters):
Point At NONE...
Visible in Render ON
Render Priority NORMAL
Visible in Simulation ON
Visible ON
Selectable ON
Display Persistence OFF
Ray Length 2.5
Opacity Scale 100%
Ray Opacity 15%
Show Base OFF
Base Opacity 15%
Show Edge ON
Edge Opacity 20%
Illumination ON
Color 255 255 255
Intensity 100%
Photometric Mode ON
Spread Angle 60
Beam Exponent 4.00
Light Geometry POINT
Height(Diameter) 10
Width 10
Two Sided OFF
Render Emitter ON
Luminous Flux(Lumen) 80000(my setting) 1500(default)
Temperature 7500K(my setting) 6500K(default)
Like I said, my only guess is they removed/replaced the Decay setting with something else, possibly Ray Length. If not, where can it be found?? Also, are there any good tutorials that explain what all of these settings do? Some of them are no-brainers, but others I haven't figured out yet.
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Comments
You cannot change decay (fall off) in Iray, only in 3DL.
Ok, thanks! I was wondering wth it was at. I guess I just need to adjust the beam length and/or Luminous Flux, right?
I don't know if it's actually possible in Iray to limit the beam length of a light source. Is there something specific you're trying to do? There may be other ways to accomplish it.
I just didn't want to have spotlights sitting practically on top of the target since things can get crowded in scenes, and the further out you move them, the less of an effect they will have on the target in renders. My solution for now is to just increase the Ray Length in conjunction with the Beam Angle(if necessary). I'm not sure if other things such as Beam Exponent would affect this or not. I'll have to play around some more with the settings and do more spot renders. Iray rendering full scenes is a lengthy process for me currently until I get a new desktop. Using a laptop with a NVidia 765M probably ends up using the CPU more than the graphics card itself.
Only thing that matters in Iray is light intensity (lumen) and distance, since the light will obey the laws of physics. In 3Delight which is a biased renderer, you can make the light do all kinds of weird things, not so much in Iray. I use 3DL, not Iray so can't help with actual settings, but in Iray also size matters:) If you use geometry for the spot, I figure size will affect intensity etc.
The only thing I can think of is to narrow the spotlight beam so it's focused on a smaller area. That way it won't light the whole scene, just the part you want it to point at. I guess it all depends on your scene and what you're trying to accomplish.