How to use emitters in Maxwell Standalone for Sketchup
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I would definitely recommend reading the Maxwell manual (both for the plugin and the main manual as well as it will help clarify alot about how Maxwell is designed to work -- you will find the links for those on the Maxwell toolbar.
You would apply emitters to geometry just as you would any other material. The general rule for Maxwell is you want to model everything as close to reality as possible (both in terms of scale and detail) however fully modeling lights (especially shiny reflectors) is generally a bad idea as that will increase render times... mostly due to the fact that you would greatly increase the difficulty of light calculation by introducing alot of "reflected caustics" to the scene. For the same reason (caustics calculation) you would not want to put your emitter behind glass or SSS materials as it will greatly increase render times.
It is also a good idea to keep the geometry for your emitter material as simple as possible -- a simple plane will render faster than a circle because it will contain far fewer triangles.
You can also use HDR/EXR images as light emitting material as well, and again this would be something that would be applied to geometry like all materials... the advantage here becomes particularly clear when you need to do something like flames/fire or want the look of the fluorescent light fixture without modelling the fixture itself.
The third option for lighting is IES files applied to a sphere -- however creation of MXM materials that use IES files is funtionality that is currently limited to MXED only. You can download the demo version of the Maxwell Render Suite to use MXED and create your own custom MXM's.
When setting up emitters it is important to remember that each emitter increases the calculations that Maxwell must perform and therefor will increase render time -- you can minimize this by designing your lighting (placement and spacing) as realistically as possible. Poorly designed lighting can greatly increase the time it takes for Maxwell to render clean.
Another trick that can sometimes be useful is to create extra "fill lights" to mimic the way a photographer would set up extra lighting to shoot studio/interior shots -- Maxwell is designed to be thought of as a mimic of photography principles in almost every way and the closer you can set up your scenes to the way a photographer would set up for a commercial photo shoot the better results you will have.
It would be a good start your Maxwell education by searching online for information on how photographers set up lighting for shots like what you want to render and mimicking their tools and techniques... the better you understand photography the better you will understand Maxwell -- most of the best Maxwell users are avid (and excellent) photographers as well.
Best,
Jason. -
If you're still confused after Jason's excellent explanation feel free to hone us in on where you're having issues and/or provide some screenshots. It's a bit unclear if you're not sure how to create an emitter material or if you've created one but don't see it in your render.
-Brodie
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Can emitters be applied to a sphere? I am talking about the standard emitters, not IES.
Applying emitter on a plane seems to work fine, but I tried applying it to a sphere (even with turning the "Spherical" UV on) but all I got was black. -
There shouldn't be an issue with applying a normal emitter material to a sphere. There must be something else going on. Off-hand, either the emitter strength is to low, your camera EV is too high, the scene scale may be off, or )as just happened to me) your normals are flipped so the backside is facing out and the emitter side is facing in.
-Brodie
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@unknownuser said:
your normals are flipped so the backside is facing out and the emitter side is facing in
That was it! Thanks
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@zoom123 said:
@unknownuser said:
your normals are flipped so the backside is facing out and the emitter side is facing in
That was it! Thanks
No prob. SU always seems to make my spheres with the normal going the wrong way. And whenever I draw a horizontal plane the normal faces down. Bothersome.
Be somewhat cautious with using spheres as emitters. The general rule is for emitters to have as few polygons as possible (so a plane is better than a cube is better than a low poly sphere is better than a high poly sphere).
In some tests I did awhile back it didn't cause a huge hit to render time and there were diminishing returns. So going from 1 plane to a cube caused a slowdown of (pulling this out of my head) 10%, a plane to a low poly sphere might be 15%, and a plane to a high poly sphere might be 18%. Those aren't real numbers but that's the idea.
Specifically, if you want to or need to use a sphere go ahead, but just try to make it as few polygons as you can get away with.
-Brodie
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Thanks for the suggestions.
I wanted to use a sphere because I assumed that this would be closer to how a real light bulb would emit light. I even thought of modeling a light bulb and having its surface being an emitter.
How can you do a spotlight with emitters?
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Well, just be careful with those bulb emitters. It's very tempting when you first get into using an unbiased renderer to not cheat at anything - but in the end everything (even photography) is some sort of a lie mixed with a little cheating. The important thing is to get the right look. If you're going to see the light bulb that's one thing - do what you've got to do. But you certainly don't want to go around using bulb emitters where it's hidden by a lampshade or up in a can light.
Take those two examples. For the lamp shade you won't see the bulb. You could save 90% of your emitter polygons by placing a "sphere" with only 12 sides rather than 60 and never know the difference. And if all that light is going through a shade with an SSS material? Forget about it. Lighting your scene with light going through SSS is bad news. It's doable if it's not a main light source in your scene and you've got some time to burn on rendering, but be careful with it.
Using a bulb in a can light, or in a parabolic reflector sort of situation as you'd need to be able to do a physically accurate spot light? Again, very dangerous. Light is light until it bounces off of a highly reflective surface at which point it becomes reflective caustics. Those can make for a nice realistic scene in the right circumstances. But if you try to light your scene with caustics (rather than direct light), it will take FOREVER to clear up the noise. I repeat: don't try lighting your scene with a bulb that's surrounded by a highly reflective surface. So if you're doing a can light, you'd probably want to just replace the bottom part with a circular emitter, for example.
One more thing to avoid. Emitters surrounded by glass. Same deal as before but now you're talking about refractive caustics which are just as bad. I THINK you can get away with AGS here as there's no refraction but you might use the Hide from GI option on the glass just in case.
I hope those tips help. If you want to share some screen shots of a specific scenario you're going for feel free to post some screen shots and we can give you some ideas on how to achieve that sort of emitter without getting too much un-needed noise.
As for how to do the spotlight - use an IES. I'm not sure if Maxwell comes with a great spot light IES off the top of my head but you can also go to Erco's website. Dig around and you'll find that each of their fixtures has an IES file you can download. They probably have one that'll fit your needs. When you apply an IES emitter to a sphere it will by default point down. I think that if you apply a map to the sphere - let's say a checkered map, associate that map with your maxwell emitter material, and turn the sphere into a group/component, then rotate that component, you can get the direction of the IES to change as well. It's been awhile but as I recall that's the method I've used.
One thing I do sometimes is use 2 emitters for a can light, for example (same could apply to a spot light). I'll use a circular emitter where the glass lens would normally be at in the can light because that's where you'd expect to see a bright light. I'll set that emitter power quite low so it doesn't contribute much light to the scene but shows up as a white spot indicating where the light is coming from. Then I'll place an IES emitter directly below that because I light the way it distributes the light more accurately, but I'll use the Hide from Camera option in Maxwell so you don't see the source but it provides the light. I can probably post a screen shot if that doesn't make sense.
-Brodie
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Thanks for the tips Brodie. So basically to create a spotlight I need IES but as Jason wrote in his post earlier Maxwell for SU doesn't support IES, only Maxwell Render Suite does.
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Oh darn, I didn't realize that. In that case your options are fairly limited. I've tried the hyper realistic route without much luck. If you can find out how an actual spotlight is created it'll work but I couldn't find a good resource. Depending on what you're doing, you could modify my last suggestion (using 2 emitters, one hidden and one visible). You could do a hidden circular emitter just above the floor (or wall) where you wanted to see the spotlight hit so it's light will pour out just on that space. Then point your visible light in that direction. It might fool the eye.
-Brodie
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It supports IES materials, but currently cannot make them -- however you can easily download the demo of the suite and use MXED that way.
Best,
Jason. -
@jason_maranto said:
It supports IES materials, but currently cannot make them -- however you can easily download the demo of the suite and use MXED that way.
Best,
Jason.ooo, good tip Jason.
-Brodie
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Isn't the demo of the suite a limited time trial? Is there a way to have unlimited access to MXED without buying the full product?
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The demo is unlimited. As I recall the only limitation is that there's a resolution limit and I think there's a watermark. But you could used it to create materials forever. Hadn't thought of that before. That's pretty brilliant. Perhaps eventually NL will release just an MXED download or include it with Maxwell for SU.
-Brodie
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Brodie, on the download page it says that there is a 30 day limit. Is there a legitimate way around that?
http://www.maxwellrender.com/index.php/maxwell_render_suite/download
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Oh, sorry about that. Either they changed it or I was just wrong. That is unfortunate.
-Brodie
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No problem Brodie. Maybe Maxwell will revise their policy on this. I understand not including IES, but the ability to create spotlights shouldn't be considered an advanced feature reserved only for the Suite. If they don't include MXED then they should at least create some other feature that would allow the creation of spotlights.
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The reality is they are always adding new features and they know that embedded IES lights were a need for the stand-alone plugin so that is likely to appear soon.
There was no need for them before the stand-alone plugin came out because anybody who had Maxwell had MXED as well and could make any material they needed at any time... this wasn't a purposeful slight to stand-alone plugin users, simply an oversight. It's still a relatively new application (a little over a month old) so there are bound to be some hiccups.
I did notice you were commenting on VRay ability with exteriors -- which Maxwell handles quite well... I am curious are we talking hypotheticals here or do you have actual projects that you need to accomplish with these tools?
Best,
Jason. -
Yes, I did notice that the Standalone app was new. If they add a few missing features then I think it will be really competitive. If they could also figure out a way for quick preliminary renders, then it would have everything I need and I would certainly buy it!
I am not a pro in 3D (neither I am planning to be - I am a Web Developer). I have one project and that is my own house which I am currently designing. I have an architect, interior designer etc, and I could also hire somebody to do the 3D for me. But I am a bit of a perfectionist and I like to evaluate many different possibilities until I find the "perfect" one. So I learned Sketchup and I used the plans to make the house in 3D. Now we moved into the phase when we have to decide about specific materials and do the lighting plans, and Sketchup by itself is not very good for this. So basically I am looking for an app that will allow me to evaluate several different possibilities for materials, lighting and other aspects of the interior design.
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Well Maxwell is the render engine for perfectionists by perfectionists -- the reason for it's reputed lack of speed (which I think is blown way out of proportion) is because they refuse to compromise in any way from their ideals... Which they say right up front on their website.
There will be no biased engine added to Maxwell, FIRE is it for previews... any speed improvements will come from upgrading to more powerful hardware and possibly some code optimization.
I respect that approach since I take a very similar one to my work -- however everyone has different priorities and it's nice that there is an option to fit just about everyone.
Best,
Jason.
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