A primary and a cache light

[Gary David Bouton]

Hi All--

I really hope that I can sit down and write a long piece on lighting, because I've yet to be in complete agreement with a lot of suggestions put forth on the work of fellow forum members.

I would just like to submit this unretouched image as an example or creative yet realistic lighting. I wanted the scene to look like morning. The obvious lighting setup should include venetian blinds to suggest morning light peeking through. So I put a directional light on the scene, and then put a bunch of vertical slats in between the light source and the table top.

Finally, I added a weak, second directional light, a red one to warm the scene, to balance and soften the scene. Sort of like ambient light reflected off white walls.

I think the lighting is more expressive than the subject matter ! [img]/infopop/emoticons/icon_smile.gif[/img]


My Best,

Gary David Bouton
Gary@GaryDavidBouton.com
Free education! The Writings Web site
and the updated GaryWorld Gallery is pretty okay, too.

[Earl]

Hi Gary,

I did not in any way mean to offend your use of Adobe PhotoShop. It is a very powerful program - one that has few rivals. I, though, find Corel Photo-Paint much more intuitive and useful - but by no means do I look down upon the use of PhotoShop. I find so many people say "PhotoShop" is the 'best', simply because it costs the most. The truth is, of course, both PhotoShop and Photo-Paint are top class 2d bitmap editing programs, and both produce professional results when in the right hands. For this reason, I often play around with PhotoSHOP's title to lightly express my view of how ignorant folks can see things... (no one in these forums).

So, again, I apologize for being misleading. I think it's humorous the little silent war between PhotoShop and Photo-Paint - thus, I often refer to PhotoShop as PhotoChop, or PhotoFlop, or even PhotoMop... but I do it in a light-hearted "no offense intended" sort of way. And again, I apologize for it being seen in any other light. [img]/infopop/emoticons/icon_smile.gif[/img]


Bret,

That is a perfect example of radiosity! The "ever-popular halogen torchiere"...I'll have to remember that and use it as an example for someone who's confused on the subject. Thanks!

[bmh216]

I use 3ds Max R4, and it's default renderer has no radiosity solution at all. So, for instance, if you have a single light source outside of a window, the room is pitch black. This is counter to nature. Light rays (photons) should, by their nature, enter the room and bounce around.

When I think of radiosity, I think of my bedroom, where my PC is located: most of the time, the entire room is lit by a single 100 watt bulb in an upwards-facing fixture (and the monitor itself). The light bounces from ceiling and walls to light the room, without any "super-black" corners of shadow.

Or consider the ever-popular halogen torchiere, where the light is directed almost exclusively on the ceiling: the room is still well lit, and this is the crux of radiosity. If the ceiling were black, the room would remain very dark. If it were pink, the entire room would take on a pink hue. This is not possible to render accurately without "cheating" with colored lights in 3ds.

As far as radiosity being a "new" concept, and no disrespect is meant here, it is by no means a recent consideration. I direct you here:

http://www.graphics.cornell.edu/online/box/

Check out the "history" link: as long ago as 1984 Cornell was obviously concerned with radiosity and its' solutions.

There is a tutorial supplied with 3ds Max that specifically shows you how to "cheat" a radiosity solution for the Cornell Box with colored lights. I simply prefer a natural bouncing of photons to a workaround.

(Sorry so long)...
Brett

[Gary David Bouton]

Scott,

is the server working? My posts this morning have been eaten!!

Cheers,

Gary David Bouton
Gary@GaryDavidBouton.com
Free education! The Writings Web site
and the updated GaryWorld Gallery is pretty okay, too.

???

[Gary David Bouton]

Dear Earl--(and everyone)--
one of the things I was taught in art school is to start with a general form, and then add the specifics. Failing students in college did not have the "big picture"...they labored over filagree work on a chair, when the general shape of the drawn chair looked like shit.

You're much wiser than I in the ways of today's modeling programs. I run out of date antique programs, but I still obey the physical rules of Art.

I have nothing against radiosity. What I DO commiserate about is the fact that it is generally perceived as a coool new tool ,and produces loftier results than its specular cousin, shadow and reflection tracing. Unless you FULLY understand what you are doing with radiosity, you get an unreal image. I remember when reflection tracing was "oh so cool" that everything that everyone did were shiney chrome balls.

Stu's shading is accurate in a certain sense, but it is not realistic, IMO. The shadows are way too dense for a dimly lit scene, and if there is only one light source, a dim one, you'd have crisp shadows at the base of objects, quickly diffusing out to nothingness. You'd never see the shadow of the top of the chair.

Now, as far as "Photochop" goes: gang, I've written 12 books on Adobe Photoshp (as my bio here says), and it's really not a tool to make light of.

Take a look at the attached file. The lighting sucks, but look carefully at the shadow of the lava lamp.

I painted *all* the shadows in, when I did this in 1995, because I didn't own a modeling program that would do shadow mapping.

Tools are terrific.
But ultimately the artist's eye is what determines the quality of the work.

My Best,

Gary David Bouton
Gary@GaryDavidBouton.com
Free education! The Writings Web site
and the updated GaryWorld Gallery is pretty okay, too.

[s.winders]

Hi Earl [img]/infopop/emoticons/icon_smile.gif[/img]


I personally am of the opinion that I dont care what kind of lighting I use as long as it does the job [img]/infopop/emoticons/icon_smile.gif[/img] I also dont know enough yet about different kinds of lighting so I just experient over and over until I get close,then I sit back and try to work out what I have done to get close to what I am looking for.Once I have worked that out then I re tweak the lighting again and usually decide what I have just ended up with is ok [img]/infopop/emoticons/icon_smile.gif[/img]


I have also started experimenting with negative lighting as well.

Is radiosity like volumetric lighting on steroids?

Cheers

Stu.

[Earl]

I'd have to disagree Gary. Even shiny surfaces have a diffuse element to them. And I do believe that just about any scene would benefit from the quality increase in shadow detail of radiosity - especially those which are trying to simulate real world lighting, or photo-like lighting. Indoor scenes especially benefit from this type of rendering...

It is computer intensive - and thus not appropriate for everything... but if you have the guts in your machine (and your 3d program) I don't think there's any scene that wouldn't benefit from it's added quality...

[s.winders]

This lighting is by no means perfect,but it is what I would think indoor night lighting would be more like.....just my opinion.


Stu.

[Earl]

Hi Stu,

I think you did a great job on your dining room scene. Gary, I also think you lit your teapot scene pretty good as well. Both accomplished what they set out for. And I don't think that 'spectacular' results can't be accomplished with radiosity...but I do know that a lot of people really oppose it. And that I can't figure out. Perhaps what they know of as radiosity isn't the same as what I know of as it...perhaps the programs they've played with that have radiosity, implemented it in a strange and less usable way. It's hard for me to say... but I do know that for the best quality image, radiosity really can't be beat...since it can give you the true-to-life subtly that just can't be achieved otherwise.