Page 1 of 2
Easy Question for the Experts
Posted: Tue Sep 16, 2008 11:45 pm
by 3ddrummer
Ok guys...This is a Stupid Question, but I need help.
Are you using light emitters from your 3D applications as the lights used for rendering? I have been just creating shapes (triangles, cubes, flat planes) to represent the actual light and going into Maxwell Studio and applying the light emitters to the shape. But ive ALWAYS had to use the brightest light 'METAL HALIDE HMI- 2500W' to get a normal lighted interior scene.
Im a new 3d renderer. I use AutoCAD to create models and use JOMAGA's method of exporting them into Maxwell Studio. I think my scale is correct using his method. ANY ADVICE IS APPRECIATED!!!!
-3DdummeR
Posted: Wed Sep 17, 2008 1:29 am
by lebbeus
Maxwell is physically based, therefore it needs actual geometry for the emitting element. So creating a plane and applying an emitting material is a correct method. Though you need to make sure that your emitters are as simple as possible, otherwise you'll be creating more noise for the engine to clear--search the site for emitter optimization techniques.
Your other lighting issue could be any number of things:
- -your scene is out of scale (which is entirely possible since you're not using a plugin)
-your camera settings are not appropriate for the type of scene; interior scenes require different camera settings than an exterior, do a search on this site or take a look at photography sites for appropriate settings
-you don't have enough lights in the scene to begin with
-you're trying to light a scene entirely by caustics (very easy in an interior scene)
-you're not letting the render cook long enough
Posted: Wed Sep 17, 2008 6:11 am
by 3ddrummer
this is going to sound crazy to you, but I have 3d-MAX but I know nothing about it, so I use it just to import Autocad models and export to MAxwell. So I dont think scale is an issue....
I use the same lighting plan that a normal space would have(also use the elec. engineers lighting plan)...
I give it looooong render times....
Not sure about the caustics...
I dont mess with ANY camera setting. So could that really be my lighting problem??
Posted: Wed Sep 17, 2008 7:43 am
by macray
This picture from Insomnia3D might help you to get an idea for the camera settings in maxwell's interior and exterior renderings.
http://pics.livejournal.com/macray/pic/0004thf4
Posted: Wed Sep 17, 2008 8:43 am
by pwrdesign
Have you adjusted the shutter and fstop values in the MXI file after the render is done?
Are you using multilight?
Can you upload a render for us to look at?
Posted: Wed Sep 17, 2008 9:52 am
by Fernando Tella
This tool might be useful too:
http://think.maxwellrender.com/dof_cue_tool-111.html
Usually I set ISO at 400 or higher for interior scenes. Just play with the parameters a bit while the render is running; you'll get the hang of it.
Posted: Wed Sep 17, 2008 9:11 pm
by lebbeus
3ddrummer wrote:this is going to sound crazy to you, but I have 3d-MAX but I know nothing about it, so I use it just to import Autocad models and export to MAxwell.
I suggest you start learning MAX, especially since you have it. It has capabilities that ACAD and MWStudio don't have, notably the texturing tools available.
Posted: Wed Sep 17, 2008 9:38 pm
by 3ddrummer
I knew that was coming next!!!
Fernando: I adjust the ISO but have never put it so high, I will now. thanks for the link
pwrdesign: I usually dont adjust the shutter & fstop. I use multilight so I adjust those...see the render I uploaded
Macray: THANKS
Any more camera settings info is appreciated guys
if I remember it was a 48h render to SL:18
Posted: Thu Sep 18, 2008 9:15 am
by pwrdesign
This is a good start, though I wouldnt spend too much time on the camera at this point.
The image feels pretty flat and dull, I think you should work some more on your materials instead. Get rid of the repeting pattern, play some with the roughness/nd values of your materials.
Overall the scene is nice lit, it just misses some "feeling"
Posted: Thu Sep 18, 2008 4:27 pm
by 3ddrummer
I would agree the image does seem flat & dull....I guess I was just trying to get an overall view of the wall and capture most of the elements. I also tried a side view and different angles, but some elements would have been obscurred. What would you suggest for more feeling, plants, people, more angled view?
The scene seems lit properly, but Im not using the appropiate light bulb fixture wattage as it would be in real life. Instead I have to use the brightest light emitter, which takes away the realistic effect of the actual lighting brightness. Any suggestions?
Posted: Thu Sep 18, 2008 6:46 pm
by lebbeus
I suggest taking all the textures off first (use an almost lambertian--80% rough, grey material, but keep any glass or mirrors), apply the correct lighting settings, then work out the correct camera settings for the scene and mood you want to create.
After you've got the scene rendering well, with the correct lighting, start applying the textures. Granted some textures will affect the overall lighting impression, but starting off with none will provide a better foundation for the finished image
Posted: Thu Sep 18, 2008 6:47 pm
by lebbeus
are those supposed to be 2x2 fixtures in the ceiling? they don't look to be the correct size if they areā¦
Posted: Thu Sep 18, 2008 7:26 pm
by 3ddrummer
Wow....I never would have thought to render with just the gray texture to get the lighting mood.....Im pretty convinced that my scene is scaled correctly. The lower right hand grid dimension says 1m (3ft.) which is the exact size of my doors. So I guess whats left is the camera settings. Could that affect my lighting that much? Im going to give it a 20 min. test render and post it for you to see with the grey texture and 60W flourescent lights instead of the 2500w metal halide im using
Posted: Thu Sep 18, 2008 8:01 pm
by Bubbaloo
So I guess whats left is the camera settings. Could that affect my lighting that much?
Camera settings affect your scene lighting just as much as emitter intensity.
Posted: Thu Sep 18, 2008 10:45 pm
by 3ddrummer

WOW....I really feel like a Newbie now......Yeah in 1.5yrs of maxwell I havent touched the camera settings and now I see the light
Lebbeus: here is a render with just grey material and glass and I used the 65w flourescents with adjusted CAMERA SETTINGS this time. Still need adjustment, but Im not using 2500w bulbs!!!
Fstop: 16
shutter speed: 50
Iso: 600
2h 05m render to SL 10.47
Thanks for the tip Bubbaloo