long render times

Support Compositing and Post Processing
1

Hi Iv been a lightwave user for about 2 years now, and have recently been spending quite a bit of time with blender, because some of the functionality is amazing-like the animation controlls, scullpting, particles, fluid etc- wow however im having a bit of a problem with the rendering times- I set up the same scenes in lightwave and blender and the setup and rendering times were as follows:

lightwave -smoothing on, raytraced shadows on, subdivision surface 3 levels…
render time 1.3 seconds

blender- everything default setup except
subsurf level 3- blenders native renderer: 31.47 seconds

subsurf level 3- yafray renderer: 2:12:16 seconds!!

that is a huge difference- is that normal?
how can I get the times down?

2

For the Blender Internal Render engine, you may try adjusting the Octree settings also, adjust the number of Parts used in the render. You will find more information about these options here: http://wiki.blender.org/index.php/Manual/Rendering_Options#Octree_resolution

3

with direct lighting both engines are equally fast, yafray Skydome is faster than Blender AO, and with FULL GI enable always irradiance cache or photons + irradiance cache

You can also try yaf(a)ray, which is a faster biased/unbiased GI raytracer:
http://blenderartists.org/forum/showthread.php?t=134906

Anyway, you have a compilation of scenes ready to be rendered with YafRay 009, I think you can learn a lot from them:
http://www.yafray.org/forum/viewtopic.php?t=1009