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prometheus
08-23-2011, 12:46 AM
I just canīt get my head around what causes the blotches and to remove it.

A simple box for a room,one area light, and Ivé gone through the radiosity guide over at http://www.except.nl/lightwave/RadiosityGuide95/index.htm

Perhaps not as as thoroughly as I should, since I canīt figure it out.

the blothes appears on the edges of the box room, so Im suspecting it has something to do with the geometry.

I tried to transfer radiosity settings from this scene over at spinquad
http://www.spinquad.com/forums/showthread.php?25361-Interior-Lighting-Advice

But it doesnīt matter..the blotches is still there.

Try it yourself and see if you can get rid of it with some setting..

Michael

Lewis
08-23-2011, 02:05 AM
Yes your geometry is wrong (you have 2 boxes at same place so if you hit merge it'll weld points and makes box back to single sided) BUT that still won't fully solve it (if you make proper box with wall thickens little thicker). LW Interpolated radiosity IS blotchy most of time, especially in this kind of scenes with closed area light. Scene you are referring too has and window opening which is then much easier to solve (for LW) and has textures on so even if there is small blotchiness you won't clearly see it :).

Easiest way to solve it quickly is to change fallow type from InverseDistance2 to InverseDistance and adjust intensity of light. Ten you can go with much lower Radiosity settings and quality settings to get fast and good results. Dunno will that be technically correct but i had lot of problems with InverseDistance2 and interiors so i swit cto this and do it that way.

Here is render and scene.

P.S. Why do people often throw in objects, scenes, images - everything in single folder ? Why is it so hard to make all in proper directories to keep the structure nice and clean :D?

prometheus
08-23-2011, 02:36 AM
Yes your geometry is wrong (you have 2 boxes at same place so if you hit merge it'll weld points and makes box back to single sided) BUT that still won't fully solve it (if you make proper box with wall thickens little thicker). LW Interpolated radiosity IS blotchy most of time, especially in this kind of scenes with closed area light. Scene you are referring too has and window opening which is then much easier to solve (for LW) and has textures on so even if there is small blotchiness you won't clearly see it :).

Easiest way to solve it quickly is to change fallow type from InverseDistance2 to InverseDistance and adjust intensity of light. Ten you can go with much lower Radiosity settings and quality settings to get fast and good results. Dunno will that be technically correct but i had lot of problems with InverseDistance2 and interiors so i swit cto this and do it that way.

Here is render and scene.

P.S. Why do people often throw in objects, scenes, images - everything in single folder ? Why is it so hard to make all in proper directories to keep the structure nice and clean :D?

yeah I noticed I had double sided created geometry, I tested with a simple box again but with rounded radius corner, that helped a little.

Also the area light, If I move it down to the center of the room, then the blotches disappears, but the closer the ceiling it is, it will become blotches again, and as you mentioned the inverse distance..If I turn that off completly..the blotches will dissapear too.
However..you canīt get a nice light panel if you do that.

Regarding your folder structure question, Was there a problem with finding one scene and one object in the same folder?:D

I used to pack the way you suggested in a scene and object folder, but have found that unecessary for simple things, and was following most other guys doing this simple one folder structure.

Thanks..for looking in to this Lewis.

Michael

Lewis
08-23-2011, 02:45 AM
Regarding your folder structure question, Was there a problem with finding

No it wasn't problem BUT LW likes it's own structure where you put objects, lights, scenes, images, radiosity and other and eventually with this system you sent file you'll have issues, especially with radiosity caching and possible network rendering or using IES lights. LW just "expects" them to be there and if they aren't LWSN skips them or pretend like using it and then you realize your network renders are broken :).

Just saying 'cot i see lot of people throw in everything without any order and then wonder sometime why radiosity caching is not working or similar stuff :).

prometheus
08-23-2011, 02:48 AM
No it wasn't problem BUT LW likes it's own structure where you put objects, lights, scenes, images, radiosity and other and eventually with this system you sent file you'll have issues, especially with radiosity caching and possible network rendering or using IES lights. LW just "expects" them to be there and if they aren't LWSN skips them or pretend like using it and then you realize your network renders are broken :).

Just saying 'cot i see lot of people throw in everything without any order and then wonder sometime why radiosity caching is not working or similar stuff :).

I agree with you, but in this case..I didnīt find it necessary, just more time to set up folder structures when Itīs not needed.
no cache was made..no IES lights or images...But otherwise, It should be done as you said.

Michael

Hieron
08-23-2011, 02:54 AM
Nah hold on, the dual sided part doesn't matter and the inverse fall-off can give issues but not here yet.
The big problem here is using a double sided Area Light that is insanely bright and against the ceiling, which then by GI illuminates the bottom. That is asking for mega issues.

The correct way to solve this is to make the area light downfacing, make a 100% white luminous poly to represent the light in the ceiling and you are done. Unifying poly's and adding bevels is nice cleanup but matters little for the GI solution.

Above suggestion cleans it to this and GI settings can be lowered alot:
97698

New files:
97699
(I hate "all files in one dir projects", but for tests like these I usually sin as well :P)


ps: AA at 10 and AS at 0.1 is a bit enthusiastic, especially here. When testing AA at 4 is fine and often for finals 10 and no AS as well. 0.1 AS won't do much after 10 AA steps anyway.. I dislike AS though. It mangles my nicely defined noise, something which NeatVideo would do a good job of removing in AE anyway in animation. And for stills, brute forcing AA is usually better for me.

edit: didn't notice you had the standard light still in there, which will illuminate the box when the box is no longer double sided. The light would need to be removed and I would remove the 5% ambient light as well. Some people say it does "magic in GI" but to me it just seems to flatten everything out. Would love to know how it does magic though.

edit2: my scene is a 10.1 scene, carefull when loading it into a 10.0 build. It will mess up your configs (easy to fix, just delete all CS info from scenefile and Layout config file, but still).

edit3: if you do really want that glow/glare look on the ceiling, it'd need faking (textured poly?) or done in post. imho

prometheus
08-23-2011, 03:09 AM
Thanks hieron, I think I tried single sided area lights and lum polys combined, but got issues with it..but anyway, you seem to have done it correctly so Big thanks!

oh this scene..screw that..just a test setup, didnīt really care about the AA setting unless It was vital for the radiosity smoothing.
This was just for the purpose of checking these blotchy issues with area lights.

Later on I would need to now the how tooīs and really understand it when Im working on this project..wich I got better results from, after the same initial issues.

http://www.newtek.com/forums/attachment.php?attachmentid=97300&d=1313045009

Thread..
http://www.newtek.com/forums/showthread.php?t=121535&highlight=gym

Michael

Lewis
08-23-2011, 03:15 AM
I agree with you, but in this case..I didnīt find it necessary, just more time to set up folder structures when Itīs not needed.

you do know that LW can make you folders automatically when you click "create directories" in Paths TAB :) - right?

prometheus
08-23-2011, 05:10 AM
you do know that LW can make you folders automatically when you click "create directories" in Paths TAB :) - right?

Yes I know that...Still faster to save to save out in one single folder thou, without things that arenīt needed.

a combo of a luminous poly or surface together with area light seem to be the best way I guess.
If I remove the area light and only use the light surface I would need to increase the luminosity quite a bit..and to much, we will have artifacts the same as with area lights.

In hierons fixed scene, you only have the light showing from the "source"
from the luminous poly, not the area light..therefore very sharp edges..unless making that surface double sided wich gives a slight glow.

I would liked to have a middle thing of the area light giving slightly
bloomed/glow edges thou.

Maybe postprocessing that glow instead...or surface glow.

Michael

Hieron
08-23-2011, 06:52 AM
I'd go for post to get the glow. Also, the really strong glow as you have in the original image or the thread you linked is (ceilinglights) is way too much.

If I check our lights in the office... it has 0 glow :)

prometheus
08-23-2011, 06:59 AM
I'd go for post to get the glow. Also, the really strong glow as you have in the original image or the thread you linked is (ceilinglights) is way too much.

If I check our lights in the office... it has 0 glow :)

Absolutly..way to much "glow" even if it was the properties of the area light itself...I knew that, and it wasīt my intention to have it that way in the end.

I tested with some very slight glow ..set to maybe 10 % or lower, in the image processing tab, and in the surface tab 100 %. might be enough.

archijam..posted some real life photage..here with some slight glow.
http://commercial.joeschneider.com/img/uploads/660P3310219-resize.jpg

Thanks for all the suggestions.

Michael

Danner
08-23-2011, 07:27 AM
Glow in a light that sits in a room with no floating particles (steam, dust) is a lens property/error so if you can't see it with a naked eye (which also has a lens) a camera might see it. To have the most control on glow, I often do a light-fixture-only render that gets overlayed in post with some blur.

prometheus
08-23-2011, 07:59 AM
just testing how the scene setup would look like for throwing in products..I usally have a completly different setup for my product renders, but always a good Idea I guess to try different scene setups.

So forget about the lightpanels not showing here, Im just testing the base setup from that scene..with slight light modifications and additions.

first image..just that top area light and a gym machine
second image..added a front area light in the same position as the camera.
Highlights are picked up in the edges of the machine beams.

Normally you should be careful thou not to place lights straight ahead I guess,to avoid a washed out image and rather use the ol left keylight, right fill light, and a rim light perhaps.

Second Image..just added a cyce...wich can/should be even rounder for smoother looks.

So thatīs only two lights and radiosity with final gather.
This machine is already rendered on a different setup much earlier, wich you can see here...
http://www.gymleco.se/Produkter/115.php

Regarding glows..I got plenty of glows ..might be my contact lenses are to old and greasy thou:D

Michael

Lewis
08-23-2011, 08:11 AM
Hmm, it's OK and getting better but you don't need closed/complete room for product setup visualizations so you might reconsider that setup ;). Actually it's better if you have it open 'coz it'll render faster and you can throw in all kind of fishers, umbrellas and reflection panels behind camera to get nice reflections and show beveled edges in full glory.

prometheus
08-23-2011, 08:14 AM
Hmm, it's OK and getting better but you don't need closed/complete room for product setup visualizations so you might reconsider that setup ;). Actually it's better if you have it open 'coz it'll render faster and you can throw in all kind of fishers, umbrellas and reflection panels behind camera to get nice reflections and show beveled edges in full glory.

Yeah thanks for the tip, but didnīt I mentioned that I usally have a different setup? so I do not have a closed room sections for product renders, the one wich I linked to is done that way with only the cyce.
hereīs the one with only cyce.
http://www.gymleco.se/Produkter/115.php

so do not get hanged up with this scene as of I would work on it for a final render, it all just began with testing the blotches issues, and now just testing how that scene might work with products.

Michael

Lewis
08-23-2011, 08:16 AM
Ye you did said, I'm just trying to point to not "waste" time (especially render time ;)) for such setup for product viz since it won't look better, nothing more.

prometheus
08-23-2011, 08:20 AM
Ye you did said, I'm just trying to point to not "waste" time (especially render time ;)) for such setup for product viz since it won't look better, nothing more.

Ahh..why o why didnīt you tell me in the first place that was what you ment:)
the render time of a few minutes for that low res sized image, well I just hit f9 and went to the loo..:) when I got back it was finished.

maybe some others might find it useful to see the stages, maybe that is why I posted it.

Michael

prometheus
08-23-2011, 08:30 AM
ARghh...You know what is wasting my Time..

one of you guys saved it under 10.1 colorspace, and I think you Hieron warned me, but I didnīt pay attention I guess.
Got myself to blame, not taking care here.

Now I got screwed up color space and Lw 10.0 canīt find the color palette...again...I havenīt installed lw 10.1 at work yet.

:cry:

Michael

Hieron
08-23-2011, 09:16 AM
I posted the fix too :)

just delete that whole CS space part ouf of your Layout/hub/modeler config file and delete it out of my scene file if you want to load it again. All should work fine again.

Completely flushing the config files works too ofcourse, but then you need to load plugins again etc.... sorry!

prometheus
08-23-2011, 10:39 AM
I posted the fix too :)

just delete that whole CS space part ouf of your Layout/hub/modeler config file and delete it out of my scene file if you want to load it again. All should work fine again.

Completely flushing the config files works too ofcourse, but then you need to load plugins again etc.... sorry!

ehh..I reflushed the configs..but I really donīt need to load the actual plugins again, just re add menu buttons/branches for some stuff of some plugins.

And setting up my shortcut keys and menu setup ofcourse..Ive saved it out now for backup later on.

Michael