View Full Version : help with interior scene!

03-15-2014, 04:50 PM
Hello to all,

I've been using lw 9.6 for some years but only for exteriors and not very often. Now i'm asked to do some interior scenes one of them of a kitchen.
As this is my first time with interiors i've reading some tutorials but at the end i getting more confused than before (probably i'm understanding it all wrong).
So right now for this image i have HDRI imageworld, 1 area light as the sun, another area light for the kitchen window and another for the living room at the back of the camera view. On some tutorials they say i'ts better to turn on Inverse-distance ^2 falloff and on other they just keep it off. What shoul be better? And the range? Should it reach the oposite walls or with 1 m it's fine?
The image was rendered with the settings shown in the attached image.
The scene will have also 15 downlights on the ceiling, but not set yet. Should i set them first before starting to change radiosity and light intensity settings. Should i use spotlights or photometric or maybe other type?

What do you think of the image. I'm i at the right path for a realistic looking image?

Would appreciate a lot if some one could give me some hints, please.
Thakyou all.


03-15-2014, 08:41 PM
Have a look at this thread:

See post #12, look at the glass in the windows & the polygon at the very edge of the terrace.

Radiosity is very slow (reason have been explained), just change Multiplier from 100% to 25% for test renders.

You should be working in Linear colour space and then inverse distance lights or ^2 work fine. With the down lights I would have twice the distance of the height of the ceiling. The actual light has to reach a surface to light it or it won't light anything, but you also need falloff. With 15 down lights try then at about 7 - 20% for each light. Spot lights are fine.

The colour of floor looks over saturated. The images you use should all look at bit dull and boring.

03-16-2014, 04:11 AM
Thanks, i'll check and try those settings, and see what i get.

03-16-2014, 03:53 PM
After a few settings changed and adding the rest of the lights this is what came out. Haven't changed the floor texture as you comented because it's not the finished one. The image took over 10 min to render with RPE 200 and 50 secondary rays, multiplier at 25%, AA 8, ive also turn the fog on as mentioned in the post you pointed.
Had to turn the center downlights quite low, as they over burn the kitchen islando counter.
Later i did another test with half the resolution (1280x720) the finished image will have and multiplier at 100% and it took over 1 hour to render, i think thats to much, as i will have to deliver 36 renders of the same view changing and combinating differente floors, walls and downlights or fluorescent tubes. Any tip to lower these times. I have an i5 with 6gb ram, i know it's not much but it's what i have.


03-16-2014, 08:23 PM
If you have a bright area that is impossible to reduce brightness you can also point a negative percentage light at the surface to suck light out of the scene. But it is better to fine tune the lights in the first place but it is not the end of the world.

Multiplier needs to be at 100% for fly throughs to minimise flicker. For stills 25% is ok. It's just when you get this low, detail will not look as sharp. So 50% maybe a compromise, but 25% may simply be good enough & generally only you will see the finer issues which is usually the case! We tend to get too picky on our own work.

Turn off reflections for any surface that simply does not need it. Where it is a boarder line issue maybe you can make those surfaces 0% reflection at well. Backs of cupboards, top of shelf above fridge, bottom of sink. The metal chair legs, as long as you are not too close, make the legs a bit brighter but turn off reflection. Reflections from reflection will slow renders.

Put all glass in a separate layer/s & make sure these layer/s are not seen by radiosity.

Put a 100% round luminosity poly on the ceiling for the down lights so they look like something.

Render Globals > Render > Ray Recursion Limit, default is 6, this only needs to be 1 number higher than the number of transparent surfaces. So for your scene I would turn it down to 3. Example: If you had 2 wine glasses in front of each other it would need to be 9.

Not so critical these days but if you can use PNG, & for bump maps etc change to grey scale as you don't need colour information.

Don't have massive 2000k images for small objects.

03-18-2014, 03:22 AM
Thanks again.
I lowered the contrast of all images used in the scene to 0.5 and it looks better but the sun light that comes from the window still burns the floor. I lowered it a little bit but dont want to lower to much as the scene will be darker. Any suggestion?
I've also read something about tone map and i've downloaded dpfilter plugin but could not get good result. Is it necessary, if so what settings to use. Maybe i should use another filter.
This image i attach has no post filters of any kind.

03-20-2014, 01:30 PM
Thanks JonW for your help, most usefull.:bowdown:
Been tweaking some of the textures and surfaces a bit and for my eyes it's almost ok. Still needs something else but can't tell what. For this last image i changed the top lights to fluorescente tubes. Tried with linear lights but they gave a lot of bright splotches all over the scene so decided to use area lights instead.
For all the tests i sent the scene to a friend that has lw 11 as with mine it took too much time to render, and seen the diference in time (right now this last image was taking over 1 hour to render with 9.6 and only 15 minuts in 11) im considering upgrading to 11.6.
So if any one wants to coment about this final image and what you think of it ill appreciate.
Thanks again to all.


03-21-2014, 05:07 AM
11.6 is not that much quicker. It just handles AA better, and you can get away with less, but if you look closely AA will need to be wound up. I would buy 11.6 for many other reasons but faster renders is not one of them.

P.S. Put a couple of coffee cups or one or two minor things (not glass) in some of the renders to add a touch of life. Your customer may not want it but it may be worth a try, it's a touch more work but it may just add that bit extra to each image.