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aniOcean
04-18-2009, 03:40 AM
Trying to learn the lighting technique these days. Play around with 1-3 lighting spot for the dusk period. I use vray for the rendering and found the shadow is a bit big and dark for it. This is my first time to test 3d lighting. Would anyone give me some direction how I need to work on more with lighting part?

1 light
http://img.photobucket.com/albums/v467/Ahmult/3-1.jpg


2light
http://img.photobucket.com/albums/v467/Ahmult/9-1.jpg

http://img.photobucket.com/albums/v467/Ahmult/8-2.jpg

3 light
http://img.photobucket.com/albums/v467/Ahmult/10-1.jpg

http://img.photobucket.com/albums/v467/Ahmult/11-2.jpg

raylistic
04-18-2009, 06:39 AM
hi po,
I am no expert but I will just give some comments.

Right now the floor looks like another piece of geometry composite into the picture. You should create some bounce light effects like global illumination and to blend it better, you can maybe reflect the wall onto the floor. Some minor reflections would help. And i think your keylight should cast a harsher shadow to determine where is the sunlight is coming from, after which using soft shadows to simulate the sky light.

Usually creating black shadows is not encourage. In production, most of the time, we render a separate shadow pass and composite.

Lastly, since i believe your light is coming through from windows, you can maybe map the windows texture like checker box to give the feel of the window. If not you can model the window using simple polygons and cast the light from it.

Hope these helps.

Cheers.

aniOcean
04-20-2009, 05:46 PM
hi po,
I am no expert but I will just give some comments.

Right now the floor looks like another piece of geometry composite into the picture. You should create some bounce light effects like global illumination and to blend it better, you can maybe reflect the wall onto the floor. Some minor reflections would help. And i think your keylight should cast a harsher shadow to determine where is the sunlight is coming from, after which using soft shadows to simulate the sky light.

Usually creating black shadows is not encourage. In production, most of the time, we render a separate shadow pass and composite.

Lastly, since i believe your light is coming through from windows, you can maybe map the windows texture like checker box to give the feel of the window. If not you can model the window using simple polygons and cast the light from it.

Hope these helps.

Cheers.

Thank you very much. These few days, I am trying to work it out with what you suggest. Those really help! But I got a few question. for the words "bounce light effects like global illuminatio". I have already turn the GI on when I render on the previous pics I posted. What else I need to notice except that part?
And I have been trying to work it out with window and the light coming inside. I found the shadow is less obvious than the image I posted. Much softer now :) But whenever I change the position of light, I cant see a light coming from the window obviously comparing to this image

http://img.photobucket.com/albums/v467/Ahmult/Window768.jpg

I was wondering any technique to make those light so real. How many light he uses or the effect is simply done in Photoshop?

Any hints are welcome :)

raylistic
04-21-2009, 03:19 PM
That is using light fog with noise and ray trace shadow.

Regarding the GI part, you might need to check your settings. One way to notice GI is to check color bleeding at the corners. Right now your floor looks really flat, with not much lighting diffuse. Maybe you can post up your lighting setup in wire frame so that others can comment more. And also the lighting passes you use.

SanjayChand
04-22-2009, 02:19 AM
In my opinion, if you want to learn how to light, then you should initially forget about GI/FG and just work on lighting with direct illumination. Try to fake GI with well placed spot/directional lights, as well as with comp tricks such as tinting ambient occlussion passes to differing hues.

aniOcean
04-25-2009, 12:32 PM
My missing images may confused your guys. Let me make it more clear now, sorry.

This is the scene shoot in perpective view.Here is my thought. I totally set 4 lighting. Light1 is the asistant light to reduce the contrast of the image. Light2 is the light on the top to simulate the indoor light. And light3 and light 4 are the main light which is supposed to be a sun light.
http://img.photobucket.com/albums/v467/Ahmult/1a.jpg

Light 1 setting
http://img.photobucket.com/albums/v467/Ahmult/lit1.jpg

Light 2
http://img.photobucket.com/albums/v467/Ahmult/lit2.jpg

Light 3
http://img.photobucket.com/albums/v467/Ahmult/lit3.jpg

Light 4
http://img.photobucket.com/albums/v467/Ahmult/lit4.jpg

Vray setting
http://img.photobucket.com/albums/v467/Ahmult/setting1.jpghttp://img.photobucket.com/albums/v467/Ahmult/setting2.jpghttp://img.photobucket.com/albums/v467/Ahmult/setting3.jpg

Final Render
http://img.photobucket.com/albums/v467/Ahmult/34.jpg

As I wanna to have a image which is shooted after school so I want to make it less bright as I can. This is the final Render without Light 2
http://img.photobucket.com/albums/v467/Ahmult/35-1.jpg

I hope my screenshots wont confuse your guys. The lighting parts are set by try and error and the rendering setting is learnt by some lighting book.

I got some questions after rendering it. There are so many noise in the image even I set the quality to high or medium. Is it coz my lighting intensity is not high enough?
And the other is that I render this picture which took me 10 - 15mins even I set it very low quality for it. Any ways to reduce the rendering time.

Hi,SanjayChand. do you mean better just using simple light setting rather than vray for testing?

Hi, Raylistic. so is there anything else I missed to post. I would try to play around light fog in the next few days. I hope I will get more ideas how to work it out from the internet. Thank you.

My english writing is not very good. It may confuse your guys ^^! Leave me a message if you confuse anything ^^

raylistic
04-25-2009, 12:49 PM
sanjay meant that u dont use GI for render. You should use lights to simulate GI.

I don't understand why do you use 2 main lights. Usually we have 1 key light and then the rest are fill lights, or to simulate bounce light. And it will probably be more helpful if you can close up to the scene. Now is a bit far to really see what is going on.

1 way for you to do lighting is to start with 1 light. See where the lighting goes, before adding fill lights. It would also be better to use a reference image to help yourself. You should get your lighting right, before you add those post effects like light fog, halo effects or light glow.

If you are new to lighting I would suggest getting Jeremy Birn's materials.
http://www.3drender.com/

His book is non software specific. The dvd is using maya, but the concepts are good for any package.

By the way, i am not a max user, so I will just give you some basic lighting concepts. If you need technical help, consult the guys at 3d max forum. But all software uses the same concept.

Hope these will help you. :)

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