{"id":382,"date":"2008-12-21T00:42:05","date_gmt":"2008-12-21T06:42:05","guid":{"rendered":"http:\/\/www.mrbluesummers.com\/?page_id=382"},"modified":"2012-01-29T01:33:51","modified_gmt":"2012-01-29T01:33:51","slug":"intermediate-mental-ray-lighting","status":"publish","type":"post","link":"http:\/\/www.mrbluesummers.com\/382\/3d-tutorials\/intermediate-mental-ray-lighting","title":{"rendered":"Intermediate mental ray Lighting"},"content":{"rendered":"

Hello everyone!<\/p>\n

Welcome to the second mental ray lighting tutorial.\u00a0 In this feature, I’ll be walking you through a typical lighting project for a scene I built for one of my Monday Movies.\u00a0 Remember that this isn’t the only way to illuminate a scene, and your render times could get pretty high.\u00a0 We’ll be using mental ray Sun&Sky to get the base lighting, followed by a few area lights to illuminate the hallway section of the render.\u00a0 I’ll show you some common settings you’ll need to set up along the way, and by the time we’re done you should have a well lit scene!<\/p>\n

You can download the starter 3dsMax Scene Here<\/a>.<\/p>\n

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Our final render.<\/p>\n<\/div>\n

Note that some of these images will have light leaks above the center divider wall.\u00a0 I didn’t notice these until I was done writing the tutorial, so please excuse the error.\u00a0 The scene I uploaded for you to start with has been fixed. In addition, at the end I changed the floor to carpet instead of hardwood, so don’t be surprised when you start rendering and notice there’s carpeting.<\/p>\n

\"Our<\/a><\/p>\n

Where the magic begins.<\/p>\n<\/div>\n

Go ahead and load up the file\u00a0 You’ll notice that there isn’t any lighting, but the materials work together pretty well.\u00a0 I’ve gone ahead and included some little details such as the coffee maker and the tree.\u00a0 However, you’re free to add anything you’d like!\u00a0 Throw in a conference table for good measure, or some blinds on the windows if you’d like to be extra classy.<\/p>\n

\"\"<\/a><\/p>\n

Our unlit render.<\/p>\n<\/div>\n

If you take a quick render, you’ll notice that the lighting is unimpressive, but the materials are right and the modeling is diverse enough to give us a good outcome once we’ve started lighting.<\/p>\n

\"mr<\/a><\/p>\n

Create a mental ray Sun & Sky light.<\/p>\n<\/div>\n

The first thing we need to do is create a daylight system in 3dsMax.\u00a0 Day-time renders are a piece of cake because most of the lighting comes from outside.\u00a0 Under the “Systems” tab of the modify panel, you’ll see “Daylight”.\u00a0 Create a daylight system by clicking and dragging to create the compass rose, followed by another drag and a click to create the light.\u00a0 If you get a dialogue asking if you’d like to use photographic exposure control, click “Yes”.\u00a0 It will yield good results and is vital for this tutorial.\u00a0 The direction of the light doesn’t matter.\u00a0 Click on “Manual” under the “Position” group in the modify panel, and you can then drag the sunlight light wherever you want.\u00a0 I recommend a glancing angle that bounces the light off the floor and wall.<\/p>\n

\"Scene<\/a><\/p>\n

An overview of the scene and setup.<\/p>\n<\/div>\n

Ignore the box you see on the open face of the building.\u00a0 It’s a little hack that lets you see inside a wall while keeping it inpermiable to light.\u00a0 That box is renderable and only casts shadows.\u00a0 The rest of the walls have a shell modifier on them.<\/p>\n

The next step is to set the daylight object to mr Sun and mr Sky.\u00a0 I know it seems like this should be on by default, but there are times when you’ll need to use IES.\u00a0 This isn’t one of them though.\u00a0 By setting the daylight to mental ray Sun and Sky, you’ll be tapping into a powerful natural lighting engine that can make just about anything look awesome.\u00a0 If you get a dialogue asking if you’d like to set the background to the mr Sky map, click “Yes”.\u00a0 It’s just a good idea if you’ve got nothing else for a background.<\/p>\n

\"Sun<\/a><\/p>\n

Setting up mental ray Sun & Sky.<\/p>\n<\/div>\n

Go ahead and take a quick render.\u00a0 You’ll see that our scene’s lighting has changed dramatically, and Final Gather is now giving us a little more depth.<\/p>\n

\"First<\/a><\/p>\n

Our first render with only the outdoor light.<\/p>\n<\/div>\n

Comparable to a real-life photograph, the exposure is adjusted to make the outdoors look reasonable at the expense of making the indoors too dark. We’ll increase the exposure shortly. First, we’ll help mental ray understand that these windows boarder the outside world, and should therefore bring in a little more light.<\/p>\n

Under the “Create” tab, under the “Lights” section, you’ll find mr Sky Portal under the “Photometric” group. The mr Sky Portal can be put in the window frames to boost the lighting, and basically earn us an additional Final Gather bounce for free.<\/p>\n

\"\"<\/a><\/p>\n

Create area lights.<\/p>\n<\/div>\n

It’s important that they reasonably approximate the window frame. It’ll take some guessing and checking, but it’s worth it. You’ll also want to enable the “From ‘Outdoors'” checkbox, if available.<\/p>\n

\"Setting<\/a><\/p>\n

Set up your mental ray Sky Portals.<\/p>\n<\/div>\n

Now that the sky portals are set up, take another render.\u00a0 Notice the difference between this and what you had before.\u00a0 The additional light is clearest on the ceiling and the blueish glow on the wall.<\/p>\n

\"Render\"<\/a><\/p>\n

Render with your new Sky Portals.<\/p>\n<\/div>\n

But the image is still too dark!\u00a0 Like I mentioned earlier, our exposure is set to make the outdoors look normal at the expense of how the indoors looks.\u00a0 Let’s increase our exposure such that the indoors looks normal and the outdoors looks blown out.\u00a0 Open your Environment and Effects window (hotkey ‘8’) and set the exposure value to 11.\u00a0 Don’t hesitate to try other values and see what you think.\u00a0 This is a very powerful mechanism for altering the brightness of your renders.<\/p>\n

\"\"<\/a><\/p>\n

Turn your exposure values up to 11.<\/p>\n<\/div>\n

Here’s what my render looks like with a value of 11.<\/p>\n

\"\"<\/a><\/p>\n

Render at an exposure value of 11.<\/p>\n<\/div>\n

We’re looking good!\u00a0 But the hallway still doesn’t have any light.\u00a0 The client won’t like that one bit!\u00a0 Let’s add some lights to the lamps hanging from the ceiling.\u00a0 Select a “Free Light” from the photometric group in the lighting section of the create panel, and place it in the light trough of one of the lamps.<\/p>\n

\"\"<\/a><\/p>\n

Place the light in the light trough.<\/p>\n<\/div>\n

In this case, we want to use long cylindrical lights like fluorescent tubes.\u00a0 We’ll need to select “Cylinder” under the “Emit Light From (Shape)” group.\u00a0 We’ll also need to alter the length and radius of the light to fit nicely in the trough.\u00a0 Finally, be sure to enable “Light Shape Visible in Rendering” so that it actually appears as a tube!\u00a0 It’ll look great with the semi-transparent material I used.\u00a0 Finally, we need to set up the shadow casting.\u00a0 Select “Raytraced” from the pulldown under the “Shadows” group, and then click the exclude button.\u00a0 You want to exclude the light troughs because otherwise they’ll create abnormal shadows on the walls.\u00a0 From the list that appears, select Cylinder02, Cylinder 03, Cylinder09, and Cylinder10.\u00a0 Sorry for the lousy naming conventions- these are the troughs.\u00a0 Finally, select Exclude from shadow casting only; we still want the troughs to light up!<\/p>\n

\"\"<\/a><\/p>\n

Set the area light parameters.<\/p>\n<\/div>\n

Here’s a render showing where we are so far. The hallway is starting to light up nicely, and the conference room looks like it might actually make meetings fun. This is really going to blow away that client, but we’ve still got a little ways to go before it’s perfect.<\/p>\n

\"\"<\/a><\/p>\n

The render's starting to come together.<\/p>\n<\/div>\n

From here, let’s bump up the mental ray settings a little.\u00a0 The Final Gather bounces are still on zero and very low precision.\u00a0 The bounces value can be changed to 1 and the Final Gather Precision slider can be moved to “Low”.\u00a0 The renders will take longer, so don’t hesitate to lower these back down until the very end.\u00a0 I’m just increasing these to get closer to my final render.<\/p>\n

\"\"<\/a><\/p>\n

Increase the Final Gather bounces for more light.<\/p>\n<\/div>\n

Here’s what the render looks like after the increases.\u00a0 There’s a little more light in the corners as the Final Gather bounce pushes the lighting into recessed corners.\u00a0 It’s a subtle, but important difference.<\/p>\n

\"\"<\/a><\/p>\n

A render after increasing bounces.<\/p>\n<\/div>\n

We’re almost done!\u00a0 I just want to add two more things.<\/p>\n

The first is a light around the corner in the hallway to show that it’s a corner and to imply that the building is larger than just what’s in the field of view.\u00a0 I accomplished this by using a “Free Light” (like in the lamps), only this time I’ll be using a rectangular area light.\u00a0 This will create better shadowing by the door, and make it look like there’s more natural light (like from the other side of the office building).\u00a0 Be sure to increase the brightness a little (I used 2000 cd).<\/p>\n

\"\"<\/a><\/p>\n

Add another area light for depth.<\/p>\n<\/div>\n

The last thing we want to do is boost up the lighting in the hallway.\u00a0 Right now we’re only seeing what the four florescent lights are generating with the help of the Final Gather bounces.\u00a0 Unfortunately, it’s a little rough between the two lamp units so we’ll want to throw in an ambient-only, standard omni light to brighten it up a bit.\u00a0 Notice that you’ll need to use an abnormally high intensity in order to compete in the photographic exposure control solution.\u00a0 If you didn’t have the exposure control on, the image would be pretty much all white.\u00a0 You can use my setting of 200 intensity, or experiment to see what works for you.<\/p>\n

\"\"<\/a><\/p>\n

Include an ambient-only light.<\/p>\n<\/div>\n

And that’s all there is to it!\u00a0 Take a look at the render below to see the final outcome. Just for kicks, I changed out the floor material for a carpet because that suits the “office” theme a little closer.<\/p>\n

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Our final render.<\/p>\n<\/div>\n

I hope you enjoyed this tutorial, and learned a little more about lighting a scene using mental ray.\u00a0 Stay tuned for my weekly Monday Movies, and, until next time, happy lighting.<\/p>\n","protected":false},"excerpt":{"rendered":"

Hello everyone! Welcome to the second mental ray lighting tutorial.\u00a0 In this feature, I’ll be walking you through a typical lighting project for a scene I built for one of my Monday Movies.\u00a0 Remember that this isn’t the only way to illuminate a scene, and your render times could get pretty high.\u00a0 We’ll be using […]<\/p>\n","protected":false},"author":1,"featured_media":4413,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[12,15,20],"tags":[31,49,2564,2569,88],"_links":{"self":[{"href":"http:\/\/www.mrbluesummers.com\/wp-json\/wp\/v2\/posts\/382"}],"collection":[{"href":"http:\/\/www.mrbluesummers.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.mrbluesummers.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.mrbluesummers.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.mrbluesummers.com\/wp-json\/wp\/v2\/comments?post=382"}],"version-history":[{"count":0,"href":"http:\/\/www.mrbluesummers.com\/wp-json\/wp\/v2\/posts\/382\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.mrbluesummers.com\/wp-json\/wp\/v2\/media\/4413"}],"wp:attachment":[{"href":"http:\/\/www.mrbluesummers.com\/wp-json\/wp\/v2\/media?parent=382"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.mrbluesummers.com\/wp-json\/wp\/v2\/categories?post=382"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.mrbluesummers.com\/wp-json\/wp\/v2\/tags?post=382"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}