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Beginner question to Interior lighting w/ vray


fashlof
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Hi there CGArchitectees :)

 

I have fiddled with making architecture visualizations, but I have a big problem with the lighting right now.

 

I have this interior scene, a vray camera, with a Vray sun as my only light. The problem is that if I keep the camera setting with shutterspeed 50 and the ISO at 300, (the vray sun multiplier is at 1.2) the windows, the sills and floor are already burned but there isn't a lot of light inside the room.

 

If I increase the sun multiplier ISO or decrease the shutter speed it will just get even bigger burns on the sills & floor. which will really mess with the texture on the floor later.

 

So I guess my question is: how do I adjust my settings to match an interior scene with a vray camera and a vray sun. or should I just drop the Idea of a vray sun altogether and just go all nuts on vray light planes?

 

I have attached an quick render of the untextured scene so you can see the problem. and please say if you need any other information.

burnedsills.jpeg

Edited by fashlof
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Make sure your glass object isn't casting a shadow and blocking the sun GI. Even though you are using a vray sun, you still need to place window lights to help boost the amount of light information entering your scene. To help ease the burn outs, use a color mapping other than linear. Many people use Reinhard. You'll need to toy with the burn value in your scene a bit. It also helps to have the sun shoot at a lower angle to get light deeper into the room.

 

Me personally, I dropped using exposure on the vray camera. During production it's a little too picky/annoying for me when I just need to get my lighting all set up. If you disable exposure you'll need to compensate on your vray sun. Drop it down to anywhere from .08 to .2. It all depends on your overall scene. Using exposure won't make or break your scene. But as I said, that is a personal preference.

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Thanks for the replay :)

 

I removed the cast shadow on the glass, switched to reinhard, placed a vray lightplane at the window, turned off exposure to see how that worked out and dropped the sun a bit. the sun intensity is now 0,05 and the vraylight is at 30. the overall lighting is better but there is still alot of burned areas at the window and door.

vrayupdate-2.jpeg

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For interior scenes especially, shader definition and renderer GI tweaks work hand in hand with overall lighting. You may need to fix them in stead of waiting till the final stage. Various materials' deflected light would surely add a good amount of illumination.

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I guess you have already tried lowering both vraylight's intensity? Try values between 2 and 10.

 

30 is really high for a window light. I typically use 6-8. Make sure you don't have a 255 white on your lights as well.

 

Are you using Vray-camera and what are your settings (ISO and shutter speed) and are you using A vray sun/a daylight system and what are your intensity on those? ( are they cranked to a 0.0X value or?)

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Are you using Vray-camera and what are your settings (ISO and shutter speed) and are you using A vray sun/a daylight system and what are your intensity on those? ( are they cranked to a 0.0X value or?)

 

I'm no expert in this matter or nothing alike, but in my last interior I used VraySun (+ Sky), set at 0.06 intensity. I also placed vray lights in my two windows, with their intensity set to 2 and 3. I also added a vray light to the ceiling, with intensity set at 1, to a spot where I needed a little more light. Then lastly, I used a regular max camera (not vray) with its default settings.

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you will have a much easier time if you use the physical camera exposure - its there to help

much less mucking around with light values once you get your base values about right.

 

also if working on a 'white model' as such (and as others have said) don't use a pure white diffuse. more of a mid grey will improve your lighting once you put textures on.

 

you should be able to light that space with a couple of vray plane lights (or vraysun/sky combo) in the windows using a 2.2 linear / reinhard combination to control burn if its a problem.

 

if you can get a evenly illuminated image without burn outs you can then adjust that contrast to your taste in post. simple lighting will generally get you the most natural / realistic result its just a matter of experimenting i think.

 

if the phys cam is throwing you off you can always lock the iso and shutter to the same value and expose using only the aperture...unless you are doing DOF in camera and are a beginner i would recommend this way.

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you will have a much easier time if you use the physical camera exposure - its there to help

much less mucking around with light values once you get your base values about right.

 

also if working on a 'white model' as such (and as others have said) don't use a pure white diffuse. more of a mid grey will improve your lighting once you put textures on.

 

you should be able to light that space with a couple of vray plane lights (or vraysun/sky combo) in the windows using a 2.2 linear / reinhard combination to control burn if its a problem.

 

if you can get a evenly illuminated image without burn outs you can then adjust that contrast to your taste in post. simple lighting will generally get you the most natural / realistic result its just a matter of experimenting i think.

 

if the phys cam is throwing you off you can always lock the iso and shutter to the same value and expose using only the aperture...unless you are doing DOF in camera and are a beginner i would recommend this way.

everything in the scene (except the windows) are a standard material with rgb value of 150,150,150. so its more greyish than white.

 

so I can set my shutter speed and ISO to 150 ( as an example) and then only adjust the f-number until I get the desired result?

Regarding the DOF: I could always adjust that later on in post until I'm comfortable with lighting my scenes properly?

and in regards to the vray material, how do I secure that they are set up for a linear workflow?

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I think you can make your materials brighter than 150. I think 120 is the value you should not get under, to not have overbright materials. I would suggest too a Reinhard color mapping with a Gamma amount of 2.2 and linear workflow on. To not risk overbright areas you can set the burn value quite low, like 0.4 or 0.2. Also make shure that your materials have proper specular settings. Use Fresnel maybe with a Ior of 3 (depending on the material) and control the amount of specular with the color in the reflectance 90 degree section of the fresnel. (Black is full reflection and white is none).

Also the architecture of your room is for shure not made for a really bright interior. I think you would have the same problems if you would take a photo in real life of such a room. So also think of doing the brightening in post work in Photo Shop or Lightroom.

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everything in the scene (except the windows) are a standard material with rgb value of 150,150,150. so its more greyish than white.

 

so I can set my shutter speed and ISO to 150 ( as an example) and then only adjust the f-number until I get the desired result?

Regarding the DOF: I could always adjust that later on in post until I'm comfortable with lighting my scenes properly?

and in regards to the vray material, how do I secure that they are set up for a linear workflow?

The f number is aperture of the camera, tell me which situation would you keep adjusting that? In stead, usually we tend to tweak the shutter speed, if need be. The film ISO is fixed until you finish and change that particular roll in the camera, (not the new digital one, but the original). And though the ISO has been somewhat implemented in the digital cameras now, its still an ambiguous issue. Changing the time film gate is open could allow more or less light onto film and that is achieved by shutter speed. Photographing with mechanical SLRs will teach many good things.

 

Secondly, the linear workflow is set in the render dialog and not in materials editor.

 

Anyway, try looking for some tutorials in this regard to hone your skills.

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