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We will make a separate area for tips and users best solutions for lightsetups but i take a first step and show you some new commands that are very handy in Kray 1.7.


First of all, preview size:
type in header "previewsize 1280,1024;"
Kray's preview window is set by default at a maximum of 800x600 even though you might be rendering to 1024x768. By typing in previewsize 1024,1100; or whatever you can customize this behaviour.



Local oversampling (experimental) typed in tailer
prerender 1,2,0.01;gradients_neighbour 0.01;
or another one
prerender 0.1,4,0.01;gradients_neighbour 0.001;

The first example will render 1 full resolution prerender 2 times if not the differences between cells are less than 0.01. If so it will only do prerender once. gradients neighbour is to controll what cells that will get more FG rays fired at or not.
In the second example it will only prerender 10% of the screen but do 4 passes until the differences among cells are less than 0.01 but it will update all cells with differences larger than 0.001 for each pass taken.

Local oversampling is maybe not an everyday tool but in highcontrast/strong indirect lights/hdri lit scenes this is VERY handy to improve quality. Try the above examples on a simple scene first and with rather low FG values like min100/max 250 and see what it does. For every pass done the irradiancemap will get smother and more detailed.

Motion blur:
Works when MB in enabled in LW and Grid or Random FullScreenAA is used in Kray.

Finalgather blur:
Very handy tool also since we can get smoother and clean results with less ray's with some of the presets it's default to 10-16 but try higher values like 32 to get rid of splotches caused by not enough rays.

ok these where the things on my mind for today. Happy Kraying.

Cool info silver!

Soft sun shadows

Here's another tip:

If you'd like to get realistic Sun soft shadows you don't need to use Area light fo r it. Instead use Spotlight and in Kray "Quality" tab turn on "Spot to Area". Now to get accurate soft shadow angle it's best to set your Sun light 1km far away (you can do that quickly by ading SunSpot modifier) and then set your Spotlight Soft edge angle to 0.55°. This is because in reality diameter of sun is about 0.55°.
This way your sun shadows should look very realistic like in the attached pic.

include command

Here's another tip:

When you have some header/tailer commands that you use often you can write them to a text file, one in each line, then you can add this command to kray header or tailer: include 'myfile.txt';

This will load all commands you have written in that file. I'm attaching a file with commands I'm using. You can modify it to your liking....

Happy Kraying!

Uncached rendering (quasi Monte carlo - QMC)

Whenever you want to get best quality render and don't care too much about render time you should use Uncached render.

You do that by turning "Irradiance caching" on the General tab off.

This will ignore all settings on the FG tab except FG threshold, min rays, max rays.
What it does is it eliminates the calculation of sample points. Instead it will use every pixel as a sample point and will fire rays from each pixel.

This speeds up setup time because you don't need to deal with splotches and shadow quality.

Uncached irradiance will produce noise instead of splotches - it's similar to Fprime or LW radiosity, but still much faster.

You control the amount of grain by turning up Fg min/max rays.

Photon estimate > Precomputed filtered for fast renders

Usualy when you render exteriors, the shadows don't need to be as detailed as in interiors. This is because in exteriors the most defined shadows come from sun, sky on the other hand produces very diffused (blurred) shadows.

Therefore it's often not needed to use Photon mapping render mode when doing exteriors.
Try switching to Photon estimate > Precomputed filtered and turn on raytrace direct light checkbox.


This will ignore FG in rendering and will only use photons for the light bounces. It will speed up renders dramaticaly.

You control the smoothness of GI by turning up the N and/or Precache blur on the Photons tab.

jure wrote:Cool info silver!

Soft sun shadows
Now to get accurate soft shadow angle it's best to set your Sun light 1km far away (you can do that quickly by ading SunSpot modifier) and then set your Spotlight Soft edge angle to 0.55°. This is because in reality diameter of sun is about 0.55°.
This way your sun shadows should look very realistic like in the attached pic.

Do you set a falloff on a sunlight and if yes, what settings do you use?

Cheers, Florian

Florian wrote: Do you set a falloff on a sunlight and if yes, what settings do you use?

Cheers, Florian

Yes I set spotlight falloff to 1km.

Windows XP memory limit

Here's a tip if you have >2GB RAM installed on your machine. By default 32bit win xp will not use any RAM above 2GB. There is a way to force windows to use up to 3GB of physical RAM though. For this to work you need to edit boot.ini and add /3GB flag.
Read more here:
http://www.microsoft.com/whdc/system/pl ... AEmem.mspx

This should allow rendering huge scenes and large output resolution.

Use of 4,8,16,32,64,128,256 your blur will be free from noise.

Lumi ball can be different.
> Backdrop options,
> add Environment,
> texture environment,
> texture procerural,
grid,
line thicknes 2,0
Layer opacity is equal to the strength of the global Light.
You can modify the color.

Great tips and tricks. This should be a sticky thread on the forums!

Use Clip maps on Leafs and Trees. This will help KR engine speed up rendering process. We use to use transparency maps and Janusz told us that clip maps are the only way to go. A little more to setup in each scene, as clip maps are not a part of the object itself, but a scene item. But a quick way to do this is to have the clip map texture already put on the transparency channel but have it unchecked, so it doesn't use it. Then just go in and copy the layer and paste it onto the clip map properties of that object.

Seems to have sped up our renders with trees and plants quite a bit so far.

Thanks for the post!