View Full Version : Lighting an outdoor scene

04 April 2010, 02:12 AM
I am still learning how to Light a scene properly. I am doing an outdoor scene for a personal project. My scene currently only have diffuse textures (wip), dont have props yet. I am starting to test out the first phrase of the lighting. I added directional light at all sides, top and bottom. As well used a directional light for my Sun direction. Added an ambient Light to soften shadows. But I feel like my shadow and lighting looks abit weird. Any suggestions and critque?

Maya- Mental Ray - raytracing

04 April 2010, 07:54 PM
If your interest is the buildings, I'd first knock down the prominence of the sky. The buildings are so dark in comparison, the first thing I see is the contrast between them and that bright blue. Also I'd lower the camera position a meter or two to get closer to a normal point of view. As it is I feel like I'm standing on top of a truck.

04 April 2010, 07:28 AM
the bright blue sky was jus the color from the Camera attribute Editor...:D change the color to grey. The camera is lower down.

04 April 2010, 11:05 AM
Since you're using Maya and Mental Ray, you should have MRSun and MRSky which are based on real measurements of daytime skies and provide great results together with Final Gather.

In your scene, the sun looks like it's a bit high in the sky which takes a bit of depth from your scene. Also, don't be afraid to crank up the intensity a bit more. Ideally it should be high enough so the illuminated bits are barely to the point of blowing out (this depends on your intentions of course, but it helps a bit with the "bright and sunny" feel).

Your shadows should be a bit harder as well, and the sun looks too yellow. What you should be shooting for is a yellow with just enough saturation to counterbalance the blue and make everything white.

Try to match the light and shadows from this image:

One sun light and an environment light (casting environment shadows) should be enough. Also notice the gradient the sky has, and the nice balance between light and shadow areas. If you have a fully lit scene it will look flat and boring until you have shadows contrasting the brightness.

04 April 2010, 08:17 PM
I didn't mind the color so much as the brightness relative to your buildings. It is now easier to see them. Next I'd move the sun around: there are some interesting shapes in the buildings, maybe you can use the sun to highlight those and at the same time use them to cast interesting shadows.

04 April 2010, 03:31 AM
Hi Ribrado,

Good start. I definitely would recommend increasing the sun's intensity. Noouch posted a good example of the contrast between sky light and sunlight. Also keep in mind that the sky emits light as well.and on a sunny day like this the sky would most likely be very blue. Another thing I'm noticing is the lack of contrast that you're ambient light is creating. Take a look at the brick building on the left side of the image. Both visible sides are the same brightness. I would expect the side facing more of the direction of the sun to be much brighter and the latter much darker with a blue tint from the sky.

Keep at it!

04 April 2010, 07:39 AM
hi guys, sorry for respond late havent been home the last couple days.

I am trying this time around the Mr Sun and Sky as you as suggested. I twited the gamma ray to decrese the sun's over blowned. With Sun and Sky I dont seems to have to do much twiting. It does look alot better.

"One sun light and an environment light (casting environment shadows)"
- From my older lighting scene, those two are enough to light the whole city? I presume the environment light is to place across the sunlight?

gregsandor - Understand, my building was darker earlier. For the sun position, I am building the whole city (inserted a map of my city), should a move the sun further away from the city or near the center for better shadow?

kanooshka - Yeah I had a hard time with brick corner being brighter than the shadow. Ambient light was abit tricky. I will try to rerender my non-Mr sky and Sun scene and play around it as suggest.

One of my question is, I want to learn how to properly light a Game level Scene with all the light nodes and bounce lights. Is the Mr Physical Sun and Sky is the way to go? Or I should continue playing around with all my light nodes?

Here is my scene lighted with Mr Physical Sun and Sky.

04 April 2010, 12:15 PM
My screenshot of using Directlighting and ambient lighting.

The areas covered by the shadow (ex: alleyway props), the shadows isnt as great as my previous post(mr sun & sky). How do I fixed something like that? Can we only have one light to cast shadow? Other than that I fixed up stuff as you guys suggested, I hope I dont forget anything. :)

04 April 2010, 12:31 PM
Your shots are getting better. The first few had an objectionable amount of fish-eye distortion. The second one in the latest series is still "pouring out of the left side of the frame" because of its apparent tilt. (No, I'm not talking about the road... I'm talking about the roof-line.)

The eye is always drawn first, just like a magnet, to the brightest and/or the most contrasty thing in the picture. From there, it wants to trace a semi-circular path back to where it comes from.

(So, in shot #1, the sky and the street are begging for attention while the composition is bee-lining with four triangles straight toward that distant building. The conflict is unresolvable. Plus ... ick! ... those converging buildings! Where's your large-format camera?) :)

We especially don't like opaque darkness: that's where the tiger is.

A broad range of tonal ranges is always problematic, and it varies depending on what your output media target is, e.g. paper, film, HDTV, other, several. Media which relies upon additive coloration works entirely different from subtractive.

Ansel Adams' "Zone System" advice still stands, and for this same technical reason which applies to all forms of media. You should own, and have carefully read, his entire series of textbooks (especially "The Negative" and "The Print") even though you are not using film at this point. (Hint: if you are going final to film-stock, "guess what!") The histogram tool should always portray a bell-curve with only a few carefully-chosen exceptions. This is what you must arrive at, no matter how you get there.

Eventually, your sharply-angled light will need to have matching shadow details, at least on objects that are prominently close to the camera. And the apparent focus of the final renders must be razor-sharp. (Welcome to "the f/64 club.") Crisp shadow detail is a primary indicator of "apparent" focus.

04 April 2010, 10:48 AM
Oh yeah it is true my shadows (especially in the alleyway) area lacked the range. My screen shots are temporary, I am planning to animated panning a few cameras around my city. Haha I am not much photographer, which why I screenshots bad angles (like I am with real camera). This is something I always wanted to learn as well, to be a better photographer and to take beautiful pictures. I will try to add my the rest of my buildings to fill up my city (cuz it is hard to find the right position with half of the city missing) and after will post more pics for cameras panning across my city, for you to critque :D.

Its the first time I have heard of Ansel Adams' Zone System, so I watched some videos on youtube and it's really interesting. So I desaturated my lasted pics and compared them to some of those Black and white photos. Their photos has so much range, and mine not so much. Which means I need to more on my lighting and the photoshop them. And thank you so much, I will read up more on this zone system to help me be a better digital artist and for sure help my scene

04 April 2010, 12:20 PM
The most critical idea, that Ansel spelled-out very eloquently, is that the tonal range of the shot is very important ... that it must conform to the physical capabilities of whatever media is going to capture the shot (not applicable in this case), and whatever media (singular or plural) is going to be used to present it.

The human eye, of course, scans a scene rapidly: "what we see" is built-up in our amazing brains, so that we're able to discern light-and-dark detail over a range of something like 22 f-stops. Color negative film, on the other hand, is about 2 stops; black-and-white maybe 3 to 3.5. Printing processes, of course, use a completely different scheme for creating color, and play by entirely different rules. Ansel didn't talk about modern digital video-monitors or digital projection systems (because they weren't invented in his lifetime), but the principles are still the same.

It's strange. Example: what's the background-color of this page? "Black, of course." Uh huh. Now turn off the monitor. What color's the screen? "Uhh, it's dark gray." "Well then, how can it be black when it's gray?" Your eye interprets "light and dark" relatively. Go figure. (Your eye is built to detect tigers, because you taste like chicken.)

When you look at the image, and "regard it" as you would do the "real" scene that the image endeavors to "be," to the extent that your eye instantly fails to do so you instantly feel that "this is not quite right" or "this is fake" but you don't necessarily understand why.

The issues of how your eye reacts to light and dark are even more subtle. The matter is at-first mentioned just in the context of "blown-out whites" and "opaque shadows," which are subliminally objectionable (the tiger...). If you exceed the rather-narrow limits of your media, that's what (very abruptly) happens. Those are, simply, errors. But, handled correctly, "light leading" is also an artistic factor. Once again, the viewer might not be aware of it. As a visual artist, you need to be very aware of it, but learn to apply it subtly enough that it is not noticed.

The lighting of a scene does not, strictly speaking, have to be "real." It must be (a) technically adequate (see above...); and (b) plausible. Especially where it matters most. But, really, there's not a scrap of "real" about any of this stuff -- not in CG, and not in (studio...) photography. "Reality" doesn't work, because media can't do what the eye does. We have to compensate for the limits of the medium or media that we use ... and, outside of the theatre, for the vagaries of usually-cheap video displays in trailer parks across the land. (For the same reason that the control-rooms of recording studios throughout the world always have "a cheap set of speakers," and now, MP3 players.)

04 April 2010, 01:58 PM
It's starting to look a lot better :)

Your environment/sky light doesn't seem to be casting any shadows at all. I'm not exactly sure how it works in Maya, but the 3ds max skylight has an option to enable raytraced shadows. Alternatively, you can render out an Ambient Occlusion pass and try to multiply it over your image in Photoshop or the compositing app of your choice (I'm sure there's some way to do this in the shader as well, but I'm no Maya person...)

Also, you might want to adjust the sun to a slightly warmer color to counter-balance the blue a bit more.

04 April 2010, 07:30 PM
:D I will finish up the rest of my evironment level and textures. I think it will be a better way for me to fix up my lighting and the compositions and other critiques you guys might have. You guys are awesome and help me alot. :D Yes I will read up more on that "zone system"

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