simplicity in lighting setup? Your thoughts

[Mister3d]

Hi.

I read that Christohper Nichols says that simplicity in lighting setup is a good thing: there should be lights that represent the light sources, and no more.

And your best friend are photometric lights, if to talk about torches, fire etc.

Also he said that he hates to make things that are wrong in terms of GI.

And this is very interesting because it makes a lot of sense if to depict a real life, not biased real lighting.

What's more, you have less lights to tweak, therefore more productive and easy work.

 

 

So before I used to add a numerous number of lights, and it ended in not realistic results - too much not defined what kind and where from lights. I now trying a more productive approach.

 

From another point, sometimes I can't achieve the effect I want and it's tempting to fake some things. Here's an example:

imagine a room where a daylight mixes with firelight from a barrel, and in one corner you have the barrel, in the second distant like in 5 meters you have an area where the light from fire mixes with daylight and you can't see the firelight. What will you do:

 

Increase the intensity of fire

 

Use a non-photometric light and play around with inverse-square decay (it has an option of the end of the decay)

 

Stretch non-uniformly the light source that it achieves the distant area

 

Add one more fake omni in the distant corner?

 

Your thoughts about simplicity of lighting setup in general and about this example are welcome.

[innerdream]

I'm not the most experienced here by any means but. I'm finding the more lights you add in an interior for example that are used to fill out the lighting the more flat the image looks. This isn't always a bad thing but it takes away from photo realism if that's the goal.

[STRAT]

it also depends on how your chosen rendering app copes with lighting.

 

in cinema, i use a low gi bounce value to keep render times respectable. this usually means i place a low light emmitting ambient omni or 3 in my scenes to help with lighting levels.

 

but generally yes, i'll only put lights in where you'd get them in real life, and keep the fill-lights to a bare minimum.

 

some peeps have literally millions of fill lights in their scenes. it's nuts. absolutely no need of them.

[Mister3d]

I use Vray 1.5, so I'm pleased with its GI. It's not that my renderer lacks of something.

Yep, I was such a peep. But there's an exception I think:a very complex scene (e.g. a matrix-like machinery, loads of hoses etc.), and you need to add rims. What will you do? It just seems impossible to do them with one or 2 lights. But maybe I'm wrong, I'm not sure.

But if to follow this simple logic - creating sources that would exist in real life, it must be the realistic way.

 

It's also interestinf if it concerns fake highlights too - whether to place them if you want or to try to adjust materials and lights instead.

[louis.cho]

Hi, I am reading a wonderful book about lightning by Darren Brooker: Essential CG Lighting with 3DS Max...fantastic.

 

I took that picture from it. you can find the original on www.kanecg.com

There is a lot of fill lights in it and they are not useless. Place all light you want to create the feeling you want. Just do it logicaly and think of render time.

[innerdream]

That image looks like a painting though. I think you'll find the more lights you use the "flatter" the image will become. The additional lights effect shadows and depth.

[Mister3d]

Hi, I am reading a wonderful book about lightning by Darren Brooker: Essential CG Lighting with 3DS Max...fantastic.

 

I took that picture from it. you can find the original on www.kanecg.com

There is a lot of fill lights in it and they are not useless. Place all light you want to create the feeling you want. Just do it logicaly and think of render time.

 

I'm not an expert in creating different styles of lighting, but I'm interested in photo-realistic, or film-like renders for now. What is the year of this book? Maybe in that time GI was too expensive, and faking bounce lights was the choice. For me it's hard to judge whether this image is realistic (and whether the creator was setting this goal) mainly because it's hard to see clearly, but just think that adding any fill light should have it's motivation, and simulate a real light source, if you want realism. Here it's most probably a fake GI and its bounces. I also think that when the lighting is good you can clearly guess what kind of light is simulated and from where. Here I'm not sure is it sunlight with skylight or not. Or a bulb. But the mood is present, so one goal is achieved for sure. What's your opinion?

(edit :just took a look at his site, there's a way better quality there, so he simulated GI anyway, and there is no need for many fills there - just the sun with alpha channel for a projection IMO)

What I like is the idea (from Christopher Nichols' Gnomon DVD about exterior lighting) is when you have not enough bounce light to try adding a reflector - just a white plane, not a source. Do you see the cool idea of it? You have GI, so actually it is correct by itself. But I guess (I'm not sure) that if you add a source, there should be an explanation for it - whether it's a torch, or a skylight, etc.

From another point in movies they fake a lot, mainly as I think when lighting characters, when they need to show the form well, so they light with projectors that simulate real-world temperatures. But if you do interiors or exteriors it's another thing. Just my guesses.

[Christopher Nichols]

Well if you are trying to get the best results with GI lighting, using real world techniques you need to look at books that tell you how to light scene in the real world such as this one:

 

http://www.amazon.com/Matters-Light-Depth-Ross-Lowell/dp/0966250400/ref=sr_1_9/104-8604190-2699149?ie=UTF8&s=books&qid=1181581209&sr=8-9

 

That book is a standard for those studying lighting in the real world.

 

Books like this:

 

http://www.amazon.com/Digital-Lighting-Rendering-2nd-digital/dp/0321316312/ref=pd_bbs_2/104-8604190-2699149?ie=UTF8&s=books&qid=1181581241&sr=8-2

 

Can be a bit more misleading, as they don't really consider GI to much... So those methods tend to use extra lights for fills and reflectors. Also does other fakes like Spec only lights. These methods work great, but are far from reality. Not to say that these methods don't work in Vray, but they tend to over-complicate the matter.

[Mister3d]

Well if you are trying to get the best results with GI lighting, using real world techniques you need to look at books that tell you how to light scene in the real world such as this one:

 

http://www.amazon.com/Matters-Light-Depth-Ross-Lowell/dp/0966250400/ref=sr_1_9/104-8604190-2699149?ie=UTF8&s=books&qid=1181581209&sr=8-9

 

That book is a standard for those studying lighting in the real world.

 

Books like this:

 

http://www.amazon.com/Digital-Lighting-Rendering-2nd-digital/dp/0321316312/ref=pd_bbs_2/104-8604190-2699149?ie=UTF8&s=books&qid=1181581241&sr=8-2

 

Can be a bit more misleading, as they don't really consider GI to much... So those methods tend to use extra lights for fills and reflectors. Also does other fakes like Spec only lights. These methods work great, but are far from reality. Not to say that these methods don't work in Vray, but they tend to over-complicate the matter.

 

Thank you for your reply Christopher!

I have the second book and recently studied it a lot, and will buy the first one too, thank you, I know you like this first one.

I know about these techniques like excluding, specular\diffuse only, fake shadows etc., so technically I use these things (but that doesn't mean I satisfied with my lighting yet), but I remember you wrote once that people tend to tweak every parameter, when indeed they don't need to. So I came to conclusion (maybe wrong) that you tend not to use these fake techniques, like if you have a scene with many metal parts for example you will try not to fake highlights but get them from the sources that you have, and will try to keep things simple. I remember in one of your DVD's you were using a deflector plane, and said that thus you didn't add one more source. I'm not sure I've got it right, sure if you want to place a highlight you may, there is no a strict rule perhaps, but I just wanted to know your approach to this. I understand that when lighting a character they use colored sources so this is a fake in real world.

I mean, I wanted to know your vision of this balance fake\real world lighting.

[louis.cho]

What is the year of this book? Maybe in that time GI was too expensive, and faking bounce lights was the choice.

 

This book first edition was 2003 and re-editing in 2006 So it's not too old for now. I agree about the accuracy of GI but my point was that it's not the only solutions and when you want a great result very fast, it's very usefull to know a turnaround.

 

What is your opinion about radiosity and scanline renderer? and what about animation production?

[Mister3d]

This book first edition was 2003 and re-editing in 2006 So it's not too old for now. I agree about the accuracy of GI but my point was that it's not the only solutions and when you want a great result very fast, it's very usefull to know a turnaround.

 

What is your opinion about radiosity and scanline renderer? and what about animation production?

 

My first "experience" was with scanline. What is good, you can make fly-through animations with static objects. What is bad, the mesh can get very heavy, so if you have a scene with half a million polys, you will get with 4(?), don't know, but so heavy you won't be able manipulate by it easily. The shaders of scanline are really old - no nice blurred reflections:mad: , no SSS, no lightshader. I'm even not sure whether it has caustics, and reflective caustics. Mental ray is much better, especially in Max 9, but I don't have it, and I satisfied with Vray a lot. In MR, AFAIK, you can't bake the lighting, so it's a pain to do animation. I spent somewhere 1 month learning MR, but in max 7 to get fresnel blurred dreflections you should apply as a base material either glass, or metal... for me that's just strange. And if to compare shaders of MR with Vray, it seems that MR is for programmers, not for an average person... hell, like one hundred parameters for SSS, and it's hard to distinguish core parameters form not so important. It's all IMO. What is strange too, on Cgtalk they have a sticky article "which renderer to choose". I liked it 3 years ago, but they didn't change their opinion that MR and Prman are the best renderers for animation which can produce fast enough results for animation (that's what emphasized) So I started a topic where said that MR seems to me cumbersome and hard to learn, and hard to achieve results for a newbie. The problem that in the article they address to a broad audience, but Jeremy Birn replied to me, that really a beginner should use different tools than a specialist. They use MR in production because it's flexible (to write shaders, which I'm sure what you are very interested with your 1 machine).

The new MR is really better, so if you want to upgrade, it worth of it... but I use Vray and completely satisfied with it. First of all, thanks to its easy and logical organisation now I better know what I want. So if I would go to MR again, I would achieve better results. But Vray has several lighting techniques which are good for some kinds of animations. So if to talk about animation, Vray is my choice. Is is simply rhetorical to me, because Vray allows to me doing animation with light at reasonable time.

 

One more thing to notice, when you start with scanline, you probably will get bad results because you don't know what you want bc of the lack of experience, and lack of very important features to present days CG. The same may be with MR. But Vray is so logically organized that you learn faster IMO. I don't say MR is bad, but I'm not sure you can benefit from it at your early stages. And MR manuals suck. But if to choose from scanline and MR there's no debate MR is better.

[Mister3d]

delete, double post.

[Christopher Nichols]

The more you use GI, the more you have to stop doing things that are not possible in the real world, like specular only lights. Keep in mind that in the real world, people fake lighting all the time... such as having a big 15k light two houses down to act like the moonlight... so those things are ok. Reflectors (both specular and diffuse) are also useful.

[innerdream]

The more you use GI, the more you have to stop doing things that are not possible in the real world, like specular only lights. Keep in mind that in the real world, people fake lighting all the time... such as having a big 15k light two houses down to act like the moonlight... so those things are ok. Reflectors (both specular and diffuse) are also useful.

 

There is an interesting article on the web about using movie lighting techniques in cg renders. So much is subjective unless your goal is to be absolutely photo real and even that is up to interpretation as all photos are not the same.

[Mister3d]

The more you use GI, the more you have to stop doing things that are not possible in the real world, like specular only lights. Keep in mind that in the real world, people fake lighting all the time... such as having a big 15k light two houses down to act like the moonlight... so those things are ok. Reflectors (both specular and diffuse) are also useful.

 

Thank you once again for your reply!

I will keep that in mind. So the best is to keep all the lights simulating real-world lights and not to fake their properties. I guess it's just a general rule, but it's quite logical.

 

Robert, can you find that article you've mentioned? I would like to read it too!

[innerdream]

Alexandr:

 

I looked but couldn't find it again, sorry.