Interior Room lighting difficulties.

[reptar]

Hi all, im trying my luck at creating an interior room in 3D Studio Max. I'm having some difficulties with the lighting. I am using a Daylight System with IES Sun/ IES Sky. I have a mr Sky Portal which is positioned outside the window facing inward, into the room. I am rendering with mental ray and have Final Gather and Global Illumination turned on. What i am finding is that if my IES Sun Intensity is too high i am getting burn out of lights coming through the door onto the floor. If i turn the intensity down (as per attachment) the burn is reduced dramatically but i am getting blotches on the walls and draws.

 

Any ideas how i might be able to get a nice consistant bright light inside without light burning on the ground?

 

Cheers!

[wasteland giant]

photoshop.

 

 

the blotches are from your FG+GI settings.

 

 

you need to up them to make the blotches go away. (up bounces from FG - it defaults at 0)

 

 

Its more critical to get rid of blotching than image brightness because you can post work that easily (levels/brightness/contrast)..etc.

[Justin Hunt]

Rather use the mrsun and sky than the ies.

 

IF your using GI&FG keep the Fg bounces @0, for more lighting detail increase the Go setttings (ie number of photons shot and the number of samples per photon.)

 

The sample size is what is causing the splotches, play with that.

 

Dont be afraid to change the exposure control settings, especially the mid and shaow tones.

 

Post your GI, FG settings etc

 

jhv

[reptar]

Here is an updated render. I seem to be getting some weird speckeling from the curtains. Any ideas here?

 

I have changed from IES Sun/IES Sky to MR Sun/MR Sky.

 

The cupboard is still a bit cloudy. I have played around with samples but not sure if i am doing this correcrtly.

 

Any advice most welcome!

[Justin Hunt]

OK some thing to definiterly change

 

FG

 

Keep Bounces @ 0 when using Photons. Any extra bounces are discarded anyway

 

Photons

 

Set a maximum Sampling radius, start @ 0.5m

I dont know how many average photons you are shooting, but start at 25000

Make sure the mr Sun has the Photon Target radius set to be just bigger than the window opening. This will focus photons into the room. Also make sure the Portal light is set to shoot photons and set to automatic.

 

Image sampling

 

Min 1 Max 16 is more than enough

 

Exposure control

 

Rather use mr photographic and play with the EV values. For interiors 10 should be fine, but play with it to get the right brighness.

 

jhv

[reptar]

Interesting information. Thanks for explaining what each setting does by the way. I have made the changes suggested, with exception to tweaking with the EV value for the exposure control.

 

Here is my render. Since changing the exposure control to photographic, my environment background image has disappeared. I have made sure that "use map"is checked.

 

Also, could you please explain how i might be able to fix the white speckles on the back wall? Also i have attached my Light Lister settings.

 

Thanks for you help!

[Justin Hunt]

can you shoot me the file (dont worrk about textures) and I'll have a look. there are a few things that aren't quite right and would be easier to explain with the model in front of me.

 

jhv

[reptar]

Could you please post you email address and i will send the project to you? I'm working on this for a client so i have to keep it restricted.

 

Thankyou!

[Justin Hunt]

sent you a PM

 

Justin

[Justin Hunt]

OK had a quick look

 

I had to use Max2009, but the principals are the same for 2008

 

1) Use Gamma 2.2 (set it for Material editor, input and output 2.2 as well)

2) Wherever possible use the Arch &Design shader (I have converted these already)

3) I turned off the little spot

4) Use mrPhysical sky shade in the background slot, for some reason the wood texture was in there

5) I dialled the FG settings right down (start with Daft preset) but upped the interpolation to 80 to smooth things out

6) The Photon settings. I think I confused you with the last settings. Set the Maxiumun Number of Photons per Sample to 500 and the Average GI Photons per light to 25000

7) The Photon Max Trace Depth to 15 (These are the actual number of bounces a Photon will make)

8) I moved the Portal light back a little

9) I am not sure what the wood floor is supposed to look like, but in changing the Gamma it got a bit saturated . Also made a fer changes to the BRDF and reflection settings

10) Changing the curtains shader from standard (wit htranslucency) to A&D with translucency cleaned them up

 

There are more tweaks that can be made to really make this sing

 

I cant remember what else I changed but if you can open the file you will be able to see what I have done. I might suggest running through the interior lighting tutorial that ships with Max. It covers a lot of the basics quite well. Also read the PDF on the Arch & Design shader in the additional help. There is a wealth of information there, I certainly learnt a lot out of it

 

JHV

[reptar]

Excellent! Will get right onto the points you have mentioned!

 

Cheers,

[reptar]

Wow, i am really happy with the improvements here. Thanks to Justin.

 

Just a few questions, is the best means of brighting up the scene, by increasing the intensity of the sky portal?

 

Also, im getting some speckels on the bed post top & end and tv cabinet. I'm guessing this is a sampling issue?

 

I have been placing the outdoors image by compositing it in photoshop. I am using MR Physical Sky as the environment. What is the best method of producing the outdoor reflection on the floor and the top of the tv cabinet?

 

That should do it for now. Thanks again, really happy with the result so far.

Edited September 16, 2009 by reptar

[PuffinViz]

Take care when cutting out your background image, i can see a halo round the edge of your tv cabinet. Good work tho, much improved

[Justin Hunt]

Easiest way to brighten the scene is lowering the EV value in exposure control. Low numbers = Brighter image and high numbers = Darker image.

The speckles are the glossie refection samples being too low, increse these.

 

Double check your horizon line, it looks a little high.

 

Looking good

 

jhv

[reptar]

Ofcourse, thankyou. Will post updates soon.

[reptar]

Apologies for the small render, but im getting some halo effects around the door after compositing. Is this due to how i am compositing the outside image over the window?

 

Any thoughts?

[SandmanNinja]

When you made your mask for the doors, did you use a feathering option? I almost always use a feather value of 2 or 3 in photoshop when marqueing selections.

[reptar]

Thanks sandman, thats a really good tip

 

Please see latest version. Any ideas on how to push this further?

 

Cheers.

[SandmanNinja]

It's looking really good now.

 

I like adding an AO render to reinforce contact shadows.

 

Here's a section from my notes on AO:

 

AO Render layer

===============

The simplest way is to place a 'mental ray' material in the 'material over ride' slot

and place an 'ambient occlusion map' in the surface slot of that material. Turn off GI, turn off FG, turn off Exposure, turn off all lights, then render to suit. [256 samples, HIGH Antialiasing setting, .5m max distance]

 

[take the AO and the beauty render into photoshop, copy and past the AO onto the beauty, it gets put on the layer above the beauty. Set it to MULTIPLY and adjust opacity]

 

There are other ways that use the AO map with lights and such but they seem a little fiddly to me!

 

The 'best' way to do AO in my opinion is to use it in scene on the A&D shader, that

way you can use the flag allowing the AO to pick up colour from surrounding materials

which gives a much more accurate AO.

[reptar]

Thanks for the Ambient Occlusion tip. It add alot of realism!

 

How might i go about adding the outside reflections onto tv cabinet and floor? (see above render is previous posting). Is there a specific reflection slot i can use for the arch & design material which can accomodate this?

 

I have a MR Physical Sky for the Environment map so my outside image displays as white when i render and therefore my reflections are white.

 

Thanks!

[reptar]

Please see attached latest version of interior room. I have tried to fix the splotches on the bed post. The samples have been risen to 128 for this material. Also, i'm getting some weird lighting on the side of the television (not sure why).

 

Any comments most welcome!

 

Thanks.

[SandmanNinja]

Looking good.

 

* I'd consider 'turning on' those lamps by the bed

* There is a light bloom on the side of the TV Stand that is facing away from the window - is there a light source over there?

* Pillows and sheets look good. They look comfy

* How do people get out that door? I see a rail and what could be a balcony through the glass, so that must be a door. Consider adding some door handles in the middle and maybe a chair on the balcony

* Maybe something resting on at least one of the night stands. A book or glass of water?

 

You'll find out that a scene is never finished - you just run out of time.

[reptar]

Thanks for the tips.

 

I'll need to define the shadow more with the doors to show it is a slide door. The handles are behind the curtain. I'll see how i go with that, may change it to having handles in the middle.

 

I would really like to have the reflections from outside showing on the ground and tv cabinet. I am not sure if i am doing this correctly but i have a mr physical sky and this is why they are showing up white. Any way i can have these reflections and still be able to composite the background in photoshop?

 

I'll look at turning on the side lights. I've heard of a website out there which lets you apply real spec light globes showing real life lighting patterns and shadows from the globe onto scene objects.

 

The lighting on the television has also got me stumped... i only have a MR Sky Portal light outside the room and an MR Daylight system. Very strange?

 

Thanks again! this reflection thing has got me stumped though argh

[reptar]

Here is my latest update. I've added a book to the side table as well as a texture to those side tables.

 

Found out what that light source was. A darn gap between wall and floor. Silly mistake!

 

I've tried working on the depth of perception for the balcony by drawing lines along the lower door frame and the upper door frame and see where they intersect. From there i drew a line back from the point of intersection to line up my railing, balcony glass, horizon. Is this a known method or doing this? Its amazing what you remember from school.

 

Still having problems with the curtains. Spent ages working through different Translucent weight/Transparency combinations with the arch & design shader. Is there a better method or tutorial out there?

 

Any other comments critics welcome. I should add a door handle as per Joels request!

Edited October 7, 2009 by reptar

[SandmanNinja]

Looks much better!

Yeah, cracks in geometry are a pain but glad the light leak is fixed.

 

Liking the book on the night stand

 

I'd still like to turn on the lamps to get "light pools" on the walls.

 

Bed looks comfy

pillows look comfy

lighting looks realistic to me