coupe test renders

[Leftover]

There's a couple of Kray tests i've done for last 2 weeks. Thanks to crisis

[done]

Perfect

Any chance i could see a larger image of the stone wash basin, how did you go about that wear and dirt on the edges, painting on UVs in PS or some other means?

[jdomingo_forum]

hi guys

i am not a kray user yet but i am always on the look for all the renderings posted here and i will say this renderings done by leftover is far the most realistic i have ever seen.
is this really done in Kray? i love johny's work too. these images is making me convince of purchasing kray. is there a demo version of kray that i can play araound?
leftover, would you be able to share your technique on producing these realistic images? i am so excited and im asking too many questions now. anyway love all your work

[Janusz Biela]

ooo very nice, but please show bigger res.

[jure]

superb!

[nico]

very good rendering!!!
the light is very natural

[giacob_forum]

superb rendering.. could u give us some more informationo.. like:
1)os amd pc spec
2) did u used nodes or not?
3) light and gi settings?
4) rendertime

[bigstick]

And render settings too please if you don't mind - these images are excellent!

[salvatore]

Congratulations! Great pictures! defects do not see ..

[Leftover]

Thanks for comments

iblagdan

how did you go about that wear and dirt on the edges, painting on UVs in PS or some other means?

Yes i had to paint texture in Photoshop over UV layout. Looks like no edge detecting nodes works in Kray.

jdomingo

leftover, would you be able to share your technique on producing these realistic images?

There's no anything special used. I learned a lot of things from this forum, especially from Johny_quick posts. As well jure's and Johny_quick's answers on my questions were big help. Most of these scenes were built from real photos. When you try to match a photo you learn that "reality" inside your head can very differ from real world This kind of exercise is really useful, despite i failed in many ways i learned some good things.

Johny_quick

but please show bigger res.

Im planning to make short animation. So i have all tests rendered in 864x480 (ntsc- square pixel). I can post these if you want.

giacob

1)os amd pc spec
2) did u used nodes or not?
3) light and gi settings?
4) rendertime

1. WinXP64, Q6600, 4Gb
2. I used nodes on very few surfaces, just because it was a case when nodes allow easier control than same thing done by layers. Nothing that can't be done by regular layers.
3. I used Area lights mostly. GI setting are quite common, nothing special. Tips that Johny_quick says in every second post are probably far more important than settings themselves
4. Renders were done in 864x720 size with 4-6 FSAA. Rendertime varies 8-17 min per frame including GI calculation phase.

bigstick

And render settings too please if you don't mind

Seetings are quite common. As is see from screenshots in this forum people are using quite close setting. More important thing is adjust them to your needs and your scene properties. You better ask Johny_quick to fill Tips and Tricks section of wiki page with good tips and tricks He is far more experienced Kray user.

[Leftover]

Few guys asked for setting and i didn't answer anyhting that may help.So I tried to describe what i learned from my short Kray experience. Please note that there are probably better ways to do things, i just don't know them yet So take it sceptical. Most of tips look obvious and most of it i dig out from this forum. I hope someone will find it useful. There it goes:

I start with setting all materials Diffuse to 80. This is “base” diffuse value. Back to past when 3D apps hadn’t GI implemented and people were using regular lights and surfacing tricks to mimic real word lighting I was using Diffuse = 60 as base. Later when LW got useable GI solution I found out that value 80 works best for me. So im using same for Kray, though maybe lower Diffuse values may give you more freedom and possibilities with Kray. I don’t have enough experience to tell that.
Later on Surfacing stage i adjust diffuse values where it needed.
Then, I set Diffuse to 0 for luminous surfaces an set Luminosity to appropriate values.
Then I add KrayQuickLWF master plugin , set Parameter to 2.2 and check Affect textures. So all image maps and color values will be converted from 2.2 gamma to 1.0 gamma (which is equal to applying 0.45 gamma to images), It will help to keep saturation and contrast of final render.

Next step I put lights to scene. And tune overall lighting. Lighting may change during surfacing phase but I need to have something to start withJ At this point you have to do Photon Estimate renders to see what’s going on with photons.
Im using area lights for windows and appropriate light types for interior lights (like spots for top lights etc.) Using Area lights for windows instead of luminous surfaces or GI sphere helps to produce better quality shadows. It works for small spaces like apartments and so on, for large spaces like retail areas or casino halls using lots area lights will lead to way longer render times.

There are tips for lights I learned:

Inverse Distance^1 works best for window area lights for many scenes.

You can balance direct/indirect lighting generated by light using KrayPhotonMultiplier motion modifier. Direct light is controlled by lights Intensity, Falloff distance and indirect light controlled by Photon power multiplier in motion modifier applied to light. This way you can avoid over bright areas near lights while keeping room well lit.

I run into some problems when tuning lighting:

When using photonmap if you have spot sunlight with Spotlight to area enabled or using area light as sun - lights are losing photons. On Photons Estimate render it looks like a lot of black spots where surface wasn’t hit by photons. Actually final image may look somewhat ok, but you will see dark splotches in reflections.

There are 2 workarounds I came with.

1. Use spot sunlight and disable Spotlight to area. This way you have hard shadows from sun source

2. Switch to lightmap mode.

When using lightmap you may run into bright spots on render. Sometimes they are seen in reflections only. These are caused by “hot”, over bright surfaces near lightsource.

There are few workarounds I came with.

1. Switch to photonmap mode. For some reason there’s no such issue, but you will have to deal with dark spots if you using area sun:) , though for scenes with no sun it will work well.

2. Move object away from bright light or move light itself.

3. Change light falloff to Inverse Distance^1.

For those who doesn’t know how falloff works: If we have light with intensity=100%, falloff distance=1m and falloff type set to Inv. Distance^1 or ^2 - then light intensity on 1m distance from light equals to 100%. For ^2 it falls off in proportion to 1/R^2, and for ^1 – 1/R.

Lets see what intensity will be in 10 cm from light. For Inv. Distance^2 it will be 10000%! For Inv. Distance^1 it will be 1000%. For 1cm distance it will be 1000000% and 10000% respectively.

That’s why changing falloff type helps with this situation.

Now about Photons tab settings. Im using mostly default settings and adjusting Global photon number, N value and Power only. (and set Caustic photons to 0 of course)

Global photons and N allow to control number of cells generated by Kray. Number of cells can be seen in render window log (something like ***Building Precomputed KD (XXXXX cells)). For these scenes i have Global photons: 500.000 – 2.000.000 and N: 300 – 800 and cells number produced is about 60k – 100k, though it read somewhere on forum that 35k would be enough for such scenes. For Power i have 0.5 - 0.8.

FG tab settings. FG Treshold = 0.001, Min rays: 200-400, Max Rays: 800 - 1200

Spatial tolerance 0.1-0.03 – lower values help with small details and contact shadows (Areas for windows help to keep this parameter high and as result faster FG calculation)

Some objects can slow down FG calculation dramatically. Curtains for example. For these you can use KraySurfaceOptions shader. Turn Control FG rays on and use something like 50, 0,01, 200. Very cool ability.

And some surfacing tips I used

For luminous surfaces behind windows I used KrayIndirectRays shader with Limit DR enabled and set to 100% or lower. It helps to crunk luminosity up to get good reflections and prevent surfaces to affect indirect lighting (since window light done by area lights already)

When your render has acceptable level of noise on surfaces with blurred reflection but one of object still appears too noisy, instead of crunking reflection quality settings up and ending up with way longer render time you can use KraySurfaceOption shader for noisy surfaces. Just enable Control Reflection blur and put settings you like.

People trying to mimic Fresnel effect by using gradient with Incidence Angle input. Ususally they use 2 keys, one for 0 degrees and second for 90 dergrees. You can improve it a bit adding third key. Im usually clicking near 90 degree key (dark area for Reflection chanel) and drag it up toward 0 degrees key. FPrime can come handy for fine tuning.

To reveal small details on some objects, like carving and recessing on doors, moldings, seams between drawers and so on, instead of cranking FG settings up im using IFW Occlusion node with sample number 10-12, Distance 0.1 and Dither Disabled.

Some textures may look too dark or oversaturated when using KrayQuickLWF if this happens im using LW’s Image Editor and adjust Saturation and Gamma values for particular texture.

For dark areas you can adjust power of bounced photons with KrayPhotonMultiplier shader. Say you can put it on dark floor surface and set Diffuse power multiplier to 2 or 3.

[bigstick]

Wow - that's fantastic! Thanks for such a detailed and comprehensive overview. Lots of this stuff has been posted before, but I don't remember seeing it presented in such a concise and detailed way. Kray is a fantastic tool, and there are a number of ways to get good results. Renders are usually great, but not always mind-blowingly stunning.

I really enjoy reading different people's observations on getting great results, and reading yours, which goes through your basic approach from start to finish is no exception.

Thanks again!

[Janusz Biela]

I hope last renders from forum mean new age for Kray...we must out of the shadow....

[jure]

great tips! I will put a link to this thread on wiki!

[ingo]

.....People trying to mimic Fresnel effect by using gradient with Incidence Angle input. Ususally they use 2 keys, one for 0 degrees and second for 90 dergrees. You can improve it a bit adding third key. Im usually clicking near 90 degree key (dark area for Reflection chanel) and drag it up toward 0 degrees key. FPrime can come handy for fine tuning.....

Thanks for the nice summary of your renderings. Regarding Fresnel you should set the third key either at 30 or at 60 degrees, that is the easiest and most useful way.

cheers

ingo

(What the heck is the sense behind those annoying questions everytime one logs in into the forum ??)