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I think the light problem had to do with the materail of the light fitting. Presently I am busy with some more modeling and the interior lights, but for now can onl work in my free time on this projet so it progress slowly
I am also having a problem with distribution rendering which I have posted.
O yeah, got msn, now just have to spent some time and get to know it.
Daforce, question about the scene...
When I opened the pool scene and rendered, the direct light was way blown out, i dont know why. diffuse and spec were both off and mult is set to 1. it seems the typical setup for caustics is to use a direct light with InV Sqauare falloff right? also there is a vray light in the scene as well, in addition to the direct light. can you tell me the basic setup and why there need to be 2 lights? why not just direct one? Also, whats wrong with using GI caustics if you use QMC and have settings? whats the difference? I think if can understand that, then playing with the acutally caustics settings as in the thread will make more sense....
thanks!
basically i use the directlight purely for casting the caustics (which is why diffuse and spec are off) and the direct lighti is the only light included in the caustics solution. the vray light is there just to light the scene and doesnt cast any caustics. the scene should render as it does in the images on the other pages but i have not tried it no the newer builds my method produces accurate caustics and rather quickly, ideal for studio/product shots
Also no reason you cant use GI caustics.. BUT... they look crap with IR map, so your stuck with QMC and LC, which will take alot longer. And I would imagine you would need high settings to get accurate caustics.. therefore longer render times.
got it..that makes sense , thanks...
so I guess by your last statement that means that if using direct light (photon) caustics, then you can use IR map and it looks ok..is that right?
yep thats why I do it because the cautics are calculated by the photons and not the GI. And you get the speed of IR.
And because your using a dedicated direct light the caustics photons are pointed accurately where you want them instead of all over the shop like they would be if you just used a vray light. Therefore less caustic subdivs/photons are needed to achieve are sharp result.
Works wonders if you have a feature caustics area, like a pool or glass full of water..etc..
ahh....that must be why if you do try to use a vray light to make caustics, its often recommended making it far away, smaller, and brighter, in effect imitating direct light rays (kind of).
great explanation..I am caustic-ing as we speak!
thanks!
oh, and I your scene is fine for the newer builds i think..
i discovered that it was a scene unit issue...in my session, the search dist displayed as 127 mm..and the caustics were blown out when i lowered it to like 5, it was fine, just like the pics.
i noticed that turning off vray GI refractive caustics did make a difference in the shadow part of the pool. that must mean there are enviroment light caustics being generated too, in addition to the direct light photon caustics...since caustics is turned off for vray light in system/lights, huh?
yep, well the water has "affect shadows" ticked, and that only works if refractive GI caustics is ticked. With affect shadows unticked or refractive GI caustics untick the only way to pass light thru a refractive object is with caustics.
i thought we WERE using caustics to get light to pass through refractive materials. I thought affect shadow was a fake way to get light to pass through if using a max light (to light the scene). Since we are generating real caustics here, why does the affect shadow need to be on? as in this example
using the direct light setup as we have been talking about, this is the result above of a glass material with affect shadows on and off. it's the same no? refractive GI is on (and IM guessing only the enviroment light is using it).
i did the same test in the pool scene and having affect shadows on or off made no difference...
Yes well we are using the direct light to get the caustics thru the water but unless you have affect shadow ticked.. any surrounding lights wont affect the water.. or whats behind.
So its up to you on that part really.. you can turn it on or off, it wont make much difference if any (depends on scene)
Basically we are generating caustics from one direct light. if thats all you want affecting the water then may as well turn it off.
I find having it on brightens it up a little just makes it look a little better. Nothing significant
Basically turn affect shadow off, and no other lights will be able to pass thru the water UNLESS they are included in the caustics solution. Turn it on and (if refractive GI caustics is ON) then those lights will be able FAKE their way thru the water
Hope that makes sense.. ... probabaly not.
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