www.kraytracing.com

I downloaded the Kray demo version, and I have to say that I realy enjoy working with it. I have som questions thou.

I have some problems getting rid of wall/cealing splotches, ive tried the default settings for interior, made lightportals for the windows and all places where light passes in from the outside. Can someone recomend a good setting? (All models are in scale)

Another thing that bugs me abit is translucensy does'nt match up with lw render.
I have a couple of whitefrosted lights with a iss lightsource. LW seems to have more accurate result in the render (when looking at the translucensy). The lw render have more detail in that area, and it also looks like Kray blurs the photons so that light spreads in to unlit areas of the frostyglass to much. Any tips/tricks on that?
Ive tried the photonmultiplyer on the lightsources but still have the same result.

Woow.. Almost forgot to say: Thanks to all that have worked with developing this fantastic renderer, and for releasing a demoversion without limitations. Awsome!! I'll invest as soon as I have the budget for it.

Pictures that show your problem would be nice..

I dont have access to them at the moment, but I'll up them as soon as I can.

Hi,there..Okej. Here is a couple of renders, one LW and one from Kray. Im using ies lights as spots.
Have a look at the difference in the tranclusency.

salv8or wrote:Hi,there..Okej. Here is a couple of renders, one LW and one from Kray. Im using ies lights as spots.
Have a look at the difference in the tranclusency.

It looks to me that you didn't setup materials properly. Could you post your room and I'll check it out and show you how to setup it properly for Kray GI rendering. If you can't share the full model then just post simplified version with your lights and simple box instead of furniture.

Hi again. Sorry for the delay..
Attaching the content dir. I have added some dpcostume lights to simulate the light radiating from the translucentmaterial to get some more light in the room. But even without the dp lights kray renders the translusentmaterials WAY bright. I can ofcourse lower the tranclusency but I guess it should match up with LW to a sertain point.
Had to remove all textures to get below the 2 meg limit.

Thanx in advance for your time and help.

I know that the "house" model is quite sloppy at some places,but its a work in progress, and I assume it should not interfear with the translucensy.

Wow you really have made a mess there. Did you know that you don't need all this complicated DPcustom lights? You can just assign luminosity to your lamp material and it will emmit light and be much much faster to setup and also to render...

What you see as a difference in translucency is simply because Kray renders translucency with GI while LW simply ignores it. This makes much better translucency effect in Kray compared to LW... So yes there is a difference but it's the difference to the better.

So what you need to do first is delete all those Dp custom lights. You really don't need them and are only slowing down your scene.

Then check your materials... White wall for example should have color about 230,230,230 and diffuse 100%. Your walls have 65% diffuse right now which means about 30% of light is absorbed and therefore your room will stay dark.

And then I see you have lightportals applied to some surfaces while you are in Lightmap mode. Lightportals will do nothing when in lightmap mode so you can delete them.

Here's the scene with those little tweaks. I only made fast test render with no AA. You can tweak it from there...

I think the reason why he is using this low diffuse settings is because, as the file name says, he is using linear workflow...

Thank you..Ill check it out. The diffuseamount is just becous in real worls no materials reflect 100% of the light that hits it. While perhaps high 60 is a tad low, but 100% sound totaly off. I have not acctually put any effortin the materials as of yet, I just thought that the translusency way so very different from what im used to. I guess I'll tweek them in to Kray levels. Is that why the lower part of the uplight is lit as well? There is no spotlight in that part of the object, and there are blocking geometry between the top and bottom.
Well.. As I said.. I'll tweek the materials to a better suited Kray setup.

salv8or wrote:Thank you..Ill check it out. The diffuseamount is just becous in real worls no materials reflect 100% of the light that hits it. While perhaps high 60 is a tad low, but 100% sound totaly off. I have not acctually put any effortin the materials as of yet, I just thought that the translusency way so very different from what im used to. I guess I'll tweek them in to Kray levels. Is that why the lower part of the uplight is lit as well? There is no spotlight in that part of the object, and there are blocking geometry between the top and bottom.
Well.. As I said.. I'll tweek the materials to a better suited Kray setup.

Yes, that is correct, material should never reflect more light than it receives. But 100% diffuse does not automatically mean it will reflect all light. The reflected component is acctually Diffuse * Color. So in this equation you can see that you can keep your diffuse at 100% as long as your color is not pure white.

For me it's much easier to adjust color and leave diffuse at 100% than to adjust both... One less parameter to worry about. Remember though that once you start adding reflection, transparency or translucency the math gets a bit more complicated. More about this you can find in manual.

About translucency - I have added a small amount of luminosity to your surface to make them appear they "glow".

Hmm.. Thnx for the reflection of the materialsettings. I've just come accustomed to never leav the diffuse at 100% do to old habbits, but you make a deacent point in youre arguments. Goint to troto work from that aspectin thesceneand see if I like the outcome. Thnx again. (Althou I still think theres something wierd about the tranclusency.)
Iknow that any given materials different channels should never amount up to more then 100%, but I think it seemes like there is to much "tranclusent effect" in the materials. I guess it I'll have to get to know the way Kray handels the materialsettings.

Thnx for all help again. You have been most helfull.

salv8or wrote:Hmm.. Thnx for the reflection of the materialsettings. I've just come accustomed to never leav the diffuse at 100% do to old habbits, but you make a deacent point in youre arguments. Goint to troto work from that aspectin thesceneand see if I like the outcome. Thnx again. (Althou I still think theres something wierd about the tranclusency.)
Iknow that any given materials different channels should never amount up to more then 100%, but I think it seemes like there is to much "tranclusent effect" in the materials. I guess it I'll have to get to know the way Kray handels the materialsettings.

Thnx for all help again. You have been most helfull.

Yes like I said before. Translucency in Kray is computed with GI. This means that even indirect light will pass through translucent surface and this acts similar to thin SSS material.

Revised the materials quickly, and the result is much better. I've never been able to get my head around LW's tranclusency,just tryal and error, but now I can assume it works as any other paremeter in the surface settings. (all settings amout up to 100%)

Good job and again, thnx for the help. Rendering a 720P frame with some higher settings. Post the result tomorow.