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Hi everyone..I wanted to try the demo of Kray ..downloaded it and read the tutorials about it but it is been almost two days since I have been playing with it ..trying to lit a simple box model radiosity ..this is the best I got out of Kray with cached irradiance ...
I would won't them to match but the light pattern in what I get is absolutely different that the one from the LW ..and the lighwave is I belive how it should look in regards to physics and realism..
So I thnik I give up for today ..I would realy appreciate if someone can help ..manage to get out of Kray the LW box sample and tell me how he did ( show parameters) ....I have attached the scene file and obkect too..
thanks

scene

Hmm. could you post your settings? I don't have 1.612 anymore so I can't render that...

here they are ..well even if u manage in 1.7 i would be curious to see the settings u will have..

Well you're settings seem to be waaay off.

First photon tab:
set global map mode to lightmap
global photons to 100.000 Received

FG tab:
never use threshodl 1.0 - this is very bad
use threshold: 0.0001
spatial tolerance 0.1 or 0.1
oversample 200% or more

Leave the rest like they are for now. Search this forum Help and tuorial section for more examples...

cheers!

thanks Jure ..but still can't get it

Increase FG rays max to 1500
Try also oversample 400%

still not ..

Okay I've downloaded your scene and tried it.
First of all I have no idea why would you want to test such a simple scene with Kray since there is no real heavy GI calculations involved. 1 bounce is enough for this scene and any render engine can do that.

Now to your scene:
I have no idea why you separated top poygon from the box? It's a good idea to model surfaces so that the edges are joined otherwise you can get light leaks. Anyways this isn't a problem in this scene but it could become a problem in more complex scene.

About settings:
if you checked any tutorial about KRay you have seen that first thing to do is to get clean precompute render. I used this settings: photons 100.000 received/lightmap N5000 Precache 50%

FG settings: you should leave this pretty much at Kray default. Only increase max rays and maybe spatial tolerance. This will reduce any splotches. Oversample can help with that also.
i used threshold 0.0001 min rays 100 max 600
spatial tolerance 0.3

Misc tab: set Area lights min 2 max4 - this will reduce grain in area lights.


A note on surfaces: 100% diffuse means 100% light will bounce == unrealistic. This is why your box looks so bright...

A question: How did u get sharp edge shadow from LW? That looks plain wrong since area light casts soft shadows...

Ok I tried to do Lightwave 9.0 compare test. But I'm not prepared to wati 1h33min for a render that Kray can do in 40seconds!

bah!

Hi Jure , thanks I lot for the time spent ..well I haven't notice I have moved the top ..also uploaded the wrong render with the spot instead of the area ....but the inside walls of the cube are what is important to me...
I have tried and been testing on such a cube cause I want to se how Kray works and is the shadow radiosity pattern correct ...it is not a question of wether it is diffcult or not ..thus I spent less time ot comparing times and rendering ...i I make tens ot renders..
..Still I would say that the render you have produced has not the same radiosity pattern of shadow inside ...I don't think it is correct though it can be used well ...
...my aim is to see if Kray can produce the LW radiosity shadow....

I'm sorry but I don't think I know what you're talking about?
What is this shadow pattern your talking about?
Kray has far more realistic global illumination then LW since it uses full bounces and treats material as real light sources too. Color bleeding and bouncing of light is much better and faster in Kray than in any Lightwave version so far.

Having said that if you still prefer Lightwave's represantation of GI then by all means stick to Lightwave.

3Djapanese wrote: ...my aim is to see if Kray can produce the LW radiosity shadow....

ofcourse it can if it is radiosity
I replied to you on the newtek forum too, here the picture you want to see ( I guess)