View Full Version : wondering if i could get a little help

08-07-2013, 03:34 PM
i'm trying to do some interior views of our company lobby for a redesign and am having some issues. can anyone tell me why i'm getting strange shadows where the ceiling meets the wall, why the light shining into the room is so grainy and how i can control the hot spots better? thanks

08-07-2013, 04:02 PM
if your using GI then shoot more rays for graininess.

Hot spots could be from too much intensity from lights.
Try using the "Linear" color space so you want have to
use high intensity lights to light the scene.

Nicolas Jordan
08-07-2013, 04:16 PM
Good old splotchies. What are your Global Illumination settings? You may want to lower your Minimum Pixel Spacing to something like 0.1 and make sure your firing enough rays. probably 256 - 512 and secondary rays of 64 - 128. Also put your light samples to at least 4 or so.

08-07-2013, 04:25 PM
these are my settings. this is kind of the first archvis thing i've done involving windows and outside lighting.


Nicolas Jordan
08-07-2013, 04:33 PM
Everything looks not bad but you may want to try setting Minimum Pixel Spacing to 0.1 and see if you get any improvement. You may also need to fire more rays but I don't normally use 4 bounces in my interiors so I'm not sure what a good number of rays would be for that.

08-07-2013, 04:59 PM
thanks, that helped with the graininess. i'm still getting the splotches and now it's really orange. that may be my light or it may be too many indirect bounces? any ideas?


08-07-2013, 05:03 PM
maybe lower your maximum pixel spacing and see if it helps

- - - Updated - - -

angular tolerance adjustment maybe also not sure what it does but its suspect because it sounds guilty

08-07-2013, 05:25 PM

08-07-2013, 05:35 PM
your AA will go hand in hand with this result as well....

I'm no real expert (watch RH vid above...) but if I were doing a base setting, I would have my light and shading samples lower, and increase my AA significantly.

08-07-2013, 05:51 PM
thanks, i'll watch that instead of jeopardy tonight.

08-07-2013, 05:59 PM
Additionally, this is worth the read:


This guide should get you rolling for this kind of work.

Or if you want to not bother with a lot of settings and have the CPU power, turn off Interpolated and increase the rays until it is not grainy.

08-07-2013, 06:58 PM
Do you get the light leaks if all the surfaces are dull grey? If you have problems here then the model is not perfectly make.

Ray Recursion limit 48? You only need one number higher the the total number of transparent surface surfaces you are looking through. eg 2 wine glasses in front of each other, 8 surfaces so a setting of 9! The "door view" 3 would be fine! (if you build the model as a fish tank the glass here only needs to be a single thickness poly) Setting of 6, 12 or higher etc do improve quality but it is with vastly diminishing returns at longer render times.

Ray Precision, cut off & samples leave as default settings 6, 0.01, 1, 1. A bit of brute force settings with rendering will solve most problems just as quick & ofter quicker. Min/Max Samples try 4 / 8 then 8 / 16 & if you really want to hammer it 16 / 32. I would use to start with unless you have another reason, Reconstruction filter Gaussian, Sample Pattern Classic, (it looks better & it can render quicker, Threshold 0.03 (0.01 is overkill if you have a good number of brut force passes, AA is getting bogged down on reasonably good surfaces wasting time where the CPU would be better concentrating on the surfaces which need to reach the cutoff threshold), Oversample 0.0 when using Gaussian or you will introduce artefacts & the render will look more noisy defeating the purpose!

Turn off unless you need them:
2 sided Area lights,
Render Lines,
Ambient Occlusion,
Directional Rays,
Use behind Test,

RPE at 400 you should just get away with if everything else is ok. But get the room rendered as grey sorted out first, then you may need to up the number to maybe a 1000.

SBR, again, 50 should be borderline ok for test renders but it will need to be about a 1/4 to 1/2 of RPE.

Back to Indirect Bounces, can you get away with three. You can up the Intensity to 110%.

MinPS setting needs to be 1, you can go smaller than 1 but it shouldn't be really be needed.

MaxPS 30

Multiplier 100% (for test renders use 50% or 25% but only for layout & positioning testing, not for lighting tests, to speed things up)

Angular tolerance, I usually have this on 10-20%

Remember in Object Properties > Global illumination, you can un-tick Use Global, So for your Sofa you should be able to lower the settings to speed up rendering.

Back to the model:

Make the floor, walls & ceiling a "fish tank" so no light leaks in or out. Perfect joins, no overlapping polys, double polys, make sure all Points are merged &/or welded, anything on the perimeter surfaces of the model, including the window frames & glass (but then put the glass in a different layer so you can have radiosity turned off for the glass, &/or for other camera purposes).

Look at Point & Poly properties "W" on the keyboard while you are in Point or Poly modes & fix all dodgy points & Polys.

If you have LWCad it has another Fix Poly function which is great!

08-07-2013, 07:57 PM
well, i built the walls and windows in vectorworks. it makes the walls separate from the windows and separate from the window trim and doors.

08-07-2013, 08:52 PM
In the real world, the junctions between walls and floors/ceilings have some sort of cover, whether it's a skirting, ceiling mould, cornice whatever.
I'd add simple geometry first to your wall joints and cover those leaky joints - and see how that works.

See in these images (and many others) how this is done.

08-07-2013, 09:36 PM
In the real world, the junctions between walls and floors/ceilings have some sort of cover, whether it's a skirting, ceiling mould, cornice whatever.
I'd add simple geometry first to your wall joints and cover those leaky joints - and see how that works.

See in these images (and many others) how this is done.
Very nice renders!

Windows & doors are a piece of cake even with a few stiles (window panels) just Knife the walls & Bevel inwards a few cm (& name the first frame surface as you go "Q"), then Bevel a second time for the frame, then a third time for the frame 90 degrees to the glass plane. Then you automatically have your glass poly.

What Color Space Options are you using? lighting & colour looks blown out. Preferences > CS
Picked Colors, Light Color, Palette Files, 8-bit Files: sRGB
Display Color Space, Output Color Space: sRGB

What Diffuse % are you using on the walls, start with 80% for white walls & for a dark timber floor say 50%.

08-07-2013, 10:54 PM

the diffuse on the walls surface node is .4 in the scaler. i may not know what the hell i'm doing.

in real life of our lobby, the wall meets the ceiling seamlessly. the joint is taped and then covered with joint compound and then painted. we live in a very ugly world in las vegas offices.

08-07-2013, 11:21 PM
I'm no good with nodes, someone else will know.

You shouldn't get any splotches if the polys in corners of the rooms are lined up. On my example the cornice & ceiling are on one layer & the walls of the lounge are on another layer. They were together in one layer originally to make sure they lined up perfectly & all the points were Welded together. Then I put the cornice & ceiling in separate layer for practicality. But they still line up exactly.

08-07-2013, 11:44 PM
Very nice renders!

JonW, do excuse me - I didn't make it clear, those are not my renders - they are images of real world lobbies as a result of a google search for "office lobbies".

um, can do that tho' :thumbsup: - well, probably not these days ;)

08-08-2013, 12:08 AM
I am always amazed at the quality of what people can do.

If one can get the time, which clients are generally not prepared to wait or pay for! Spending time on details & looking very carefully at similar real life situations makes a hugh difference to a model. Even just repositioning a camera a touch can make a hugh difference.

In the thread. A simple thing like having the "right" Lobby Sofa instead of the "wrong" Lobby Sofa will make or break an image. Something in the foreground & an air-conditioning duct & safety exit sign adds distractions. Similar soft shadows the same width as the Sun will make everything fit together.

08-08-2013, 12:10 AM
Just re-read my original post - now I'm seriously silly.
What a dill, me.

08-08-2013, 12:22 AM
these are my settings. this is kind of the first archvis thing i've done involving windows and outside lighting.


I always start off with one bounce and work up from there. Some things that would really help is using Sunsky plugin. http://dpont.pagesperso-orange.fr/plugins/Sunsky.html

Use all the light types in the plugin. Add the lights sun, sky and portal. Place the portal light along the outside of the windows and scale it to the size of them to cover them from the outside. Portal lights push the environment into the room. You can use more than one but usually use one per window facing direction. Make sure you add the volumetric sky plugin also. Place the distance multiplier in the volumetric plugin to 0.1. Make sure that you set all the lights to white and 100% that way the plugin will control the color correctly. Make sure you turn the ambient light to 0% and don't use any other lights just yet.

Then set the shading samples to 1 and light samples to 1 in the render panel. Turn off functions you do not need unless you have them in the scene like render lines, lens flares and shadow maps. Set the ray recursion and ray precision to 6 and the ray cutoff to .001. Under the GI set bounces to 1, Rays 250. Turn off use gradients, use transparency, directional rays. As for the background if attached to and object, under object properties make sure cast shadows, recieve shadows, self shadow and effect GI are off. Under the lights tab in the object panel turn off all the lights from effecting the object. Set the surface luminosity for the background to 100%.

Under the surfaces for you floor set a reflection gradient to incidence angle with settings 20% at 0 and 0% at 90. Under the environment tab for the surface set the reflection blurring to 6% to start. I would copy this gradient and past it on all the surfaces and adjust the % at 0 based on the surface type it is. So say the wall to 1%, couch wood to 8%, couch to 1%, frames to 1%, etc. Set the glass to 97% transparent, Diffuse 5%, color to a tint like 96.96.96, reflection to 100% with no reflection blurring. Chrome looking stuff use the gradient and place 0 at 100% and 90 at 30%, reflection blurring to 2%.

When using VPR set it's options to draft mode and half resolution. Hit F9 and you should see a much cleaner and more realistic look to the rendering. At this point it is playing with the settings. You will find that one bounce is fine since now you have portal lights pushing the environment into the room. And make sure that you have your Colorspace settings set to sRGB.

Hopefully this helps.

08-08-2013, 10:46 AM
well, i went and rebuilt the entire room out of a solid. i just booleaned (sic) out the interior, window frames and windows. that seemed to clear up the splotches.

thanks for the help on that.


08-08-2013, 12:14 PM
Newtek should make it where Indirect Bounces can also be adjusted for each
surface individually instead of having to use diffuse to simulate this control.

08-08-2013, 02:37 PM
newtek should do a lot of stuff, but at least they answer emails and the community here is pretty good.

can't say the same for kray. it's totally unusable on the mac and i can't get any response from other users or the creator. waste of money

08-08-2013, 04:04 PM
We use lower diffuse levels on surfaces and gain up the radiosity solution. sometimes up to 300%. Your render is looking nice. Fun to see the progress of projects eh? I always look back at my first renders of a scene and then to the final render... :)

08-09-2013, 10:29 AM
it's getting better. luckily i do have processing power. it's still up to about 20mins.


08-09-2013, 05:55 PM
just some thoughts on the architectural design -

08-09-2013, 08:43 PM
yeah, i see what you're saying. those things exist already and we're not changing that. we're only doing interior work. this is pre-vis work for an actual remodel. thanks, though. i'll post an actual picture of the lobby tomorrow.

08-09-2013, 10:28 PM

08-10-2013, 04:32 PM
116280actual photo

i'll probably match the light fixtures.

08-10-2013, 08:03 PM
I personally would brighten up the render. Our eyes/brains are very good at filling in the gaps & what we don't want to see, difference in light levels from inside to outside. Difference in colour temperature. You may want to keep the render similar to the photo but I would always lean towards what our brains are capable of seeing & like to see.

08-10-2013, 08:32 PM
Hi pdrake,

My approach is a bit counter intuitive but take a look at the interior images in my signature. If you like them, this is my approach:

bounce : 4 to 6
primary RPE: 500
secondary RPE : 250

Minimum spacing : 3
Maximum spacing : 10-20
Multiplier: 25% !!

What you get is a very nice and smooth global illumination effect but with wash out details in the corners.

Use dp occlusion and filter nodes to generate a nice occlusion pass separately and blend them in photoshop using multiply mode.

Hope this helps

08-10-2013, 09:04 PM
I've spent a lot of time testing different settings, what works for me is this:

Bounce 3 -after that, it's hard to see inprovement but the time still increases
Primary 800 -this can be reduced on some scenes and needs to be increased on other scenes, depends on your geometry and the number of light sources, the more light sources the less rays you need.
Secondary 400 -usually set this to half of primary
min spacing 3 -this is a good compromise on time/quality. if you go down to 1 you would need to increase the primary rays also, or you could get smal splotches in corners.
max 100 -personal preference, 100 is clean when I use the other settings described here.
muntlyplier 100 -Going below 100% makes it faster but comparing different %s back to back I can find places where lower is not as precise as if you leave it at 100. Higher is not really worth it.

This settings are slower than Sukardi's settings. But if you set your frame interval to 15 the cache pass for a typical scene is done in under two hours (even if the fist frame takes 15min). Then lock the cache before you hit f10 so there will be no more time spent on radiosity when you render. I do have a fast machine but my render times after cache are usually under 4 minutes per frame, sometimes under a minute.