Review of "The dark art of mental ray" Tutorial

The dark art of mental ray from SimplyMaya provides workflows intended to harness the power of render layers and passes to gain minute control over your renders. This frees you from the time-consuming process of tweaking your lighting and materials to absolute perfection within Maya.

The instructor starts by briefly covering the practical implications of linear and non-linear workflows. These topics overlap with the beginning of “PhysicallyAccurate Lighting in mental ray”. Linear lighting is an abstract concept and difficult to get your head around. This is compounded by the fact that there are numerous ways to tackle linear lighting (as with all things) in Maya. The methods given are decent, but I would have liked a bit more explanation for these, since I previously learned yet another method that makes more sense, to me at least.

The explanations of render layers and render passes are excellent. It can get very confusing when and where to use either render layers or passes, and the instructor provides helpful examples of getting results from passes, layers, and combinations of the two. Case in point, you can get ambient occlusion from a render pass or a render layer, but one of them gives you much more control. Also discussed here are layer and material overrides, accessing passes from the render viewer, selecting passes to rebuild a beauty pass, and a few pitfalls. This is important information for any serious Maya user to know.

As an aside, I find that rendering tutorials often use uninspiring geometry and scenes *cough* torus knot *cough*, and while that does get the information across, it becomes easier to imagine how principles can apply to your own projects when interesting and attractive examples are used, as in this tutorial.

I have never used Nuke before; this was my first look at it. I have quite a bit of experience learning complicated software, so it wasn't too difficult for me to keep up in the compositing sections. However, the tutorial does assume some knowledge of Nuke (and Maya), so I would not recommend this for beginners in either program. Linking the separate passes in Nuke to rebuild the rendered image shows how you can gain control over your render in post, especially with higher bit files. This is the main focus of the Nuke sections of the tutorial, i.e. linking nodes together to recompose your rendered image while gaining more and more granular control over each aspect of the image. The instructor doesn't go into depth on what attributes you can or should tweak in terms of color correction etc., but this isn't the aim of the tutorial, for better or worse.

In the same vein, creating separate render layers for each light (with associated passes) really gets to the heart of controlling your output. The Nuke setup gets more involved, but it is obviously worth the effort when you see the control you have. It doesn't stop here, as contribution maps can be built to break down the scene in terms of geometry and materials. More control—is the theme becoming clear? As contribution maps and light layers are dealt with separately, I admit I am a bit unclear on how they can be used in conjunction, for the simple reason that different types of merge nodes would have to be used in a specific order in certain groupings. Just a quick look at a network with both light layers and contribution maps would clarify this for me.

Requirements for even more granular control allow us to see how to output to custom render passes, a very helpful technique. Learning how to properly add ambient occlusion passes was another eye-opener. This is all about using mental ray the right way and to maximum effect. Finally we get to see how to create material id passes; I'm not sure how the method described compares to another method I've used with surface shaders as material overrides—perhaps just passes vs. layers?

This tutorial is all about workflows for getting more out of your renders without endless re-rendering. It is abundantly clear that hitting batch render does not need to be the final step before delivery. Granular control without additional render time is a wonderful thing. But what is the cost? The instructor did not mention it, but I suspect it is disk space. Adding dozens and dozens of passes and layers adds up to eyebrow-raising file sizes. Each frame can quickly become very hefty, and even a short animation will be massive. But space is cheap and time is expensive; you can do the math.

One final thought: I am fairly confident all of the techniques shown in Nuke could be applied to After Effects, though it may be less elegant or quick to do. As I suspect more people are familiar with After Effects, I would be interested to see an addendum or short tutorial on connecting up a couple of light layers each with the required render passes. Plus ambient occlusion with the proper math. Regardless, this is an excellent tutorial that will make you think about rendering differently. I know I will be adopting many of these workflows in my current project, now that I've bought a couple more hard drives.

"Physically Accurate Lighting in mental ray" from Simply Maya

I have the privilege to review a tutorial from Simply Maya called "Physically Accurate Lighting in mental ray". This is a 2.5 hr tutorial designed to get you up to speed on using the physical sun and sky system and other indirect lighting principles to light interiors (and exteriors). The tutorial starts with a solid explanation of linear workflow, which I have heard a lot of enigmatic references to but never had the courage to tackle. While the descriptions and demonstrations of linear lighting and gamma correction far from satisfied all my questions, I now feel like I have enough to go on and I will definitely try to use linear workflow on any future lighting projects. I am also curious to explore Gen's PMM Linear Lighting Buddy plugin.

The goal of this tutorial is to create a lighting setup that can be very easily modified for light at any time of day. As such, physical sun and sky figures prominently. Portal lights, final gather, and global illumination are all utilized to supplement the main lighting provided by PSS. I found the explanations of PSS and portal lights to be more detailed than FG or GI. FG and GI are often described more in many introduction to lighting tutorials.

After setting up the lighting system, the room is textured using mia_material_x and misss_fast_shader2_x exclusively. I found some of the shader connections to be quickly done and confusing, but they ended up being repeated several times, so it becomes clear what is being arranged. There are several good tips and tricks offered to both optimize render time during testing and also improve quality in the final render.

To summarize, this tutorial is not a lighting basics course. It assumes a good understanding of maya's interface and general lighting principles. The main purpose of the tutorial is to take lighting in mental ray to the next level of accuracy and realism. Explanations are well articulated, while leaving room for further study (much like a lecture can be supplemented with textbooks). The final render is rather pleasing, and it is easy to imagine applying very similar workflows to many kinds of projects. I'd highly recommend this tutorial for anyone wanting to explore linear lighting techniques and physically accurate setups.

Thanks for reading.
Stuart

Surfing with the Alien Review

Surfing with the Alien (Vol. I) is an organic modelling tutorial from SimplyMaya.com by Jason Edwards.

Banner from SimplyMaya.com

Right up front, the final verdict (cause the full review is admittedly lengthy):

This modelling tutorial is well structured and presented and, while not for beginners to Maya, is great for people who are reasonably new to organic modelling. The vertex tweaking and topology adjustments could have used more verbal explanation, but the UV mapping sections were very helpful and surprisingly painless.

A couple notes about software and structure:

I completed this tutorial using Maya 2012 student version. The tutorial was created using Maya 2011, however I suspect much earlier versions of Maya could handle this tutorial no problem. There were few if any modelling tools or commands used that are new additions to Maya, although the UI is a bit different and may cause some confusion if you are following the tutorial using Maya 2009 or earlier. There are now two other volumes in the Surfing with the Alien series dealing with texturing, detailing in zbrush, and rigging. This review just deals with the first volume, i.e. modelling and UV mapping.

The tutorial is about 10 hrs long and is split into 16 logically defined chapters, each 30-45 minutes long. It includes image planes for the alien (but not the surfboard) along with a scene file showing the final model posed on the surfboard. The video files are quite sizable and the whole thing weighs in at over 2GB. Just something to keep in mind if you are bandwith limited.

And my thoughts on the tutorial:

The tutorial starts off with setting up image planes, which is good because knowing how to do this properly shouldn't always be assumed. From there, things get moving fast. I like to work on the project at the same time as the tutorial is playing on my second monitor. My ideal situation would be to have to pause the video rarely and rewind never. While I could almost keep up in general, pausing on occasion, I have to start off by saying that this tutorial is not meant for people new to Maya, 3D, or modelling. Although the suggested level stated on SimplyMaya.com is beginner, I think this is overly optimistic. Many tools and commands are used without being introduced (wireframe and shaded modes, extruding, inserting edge loops, split poly, working in the outliner and channel box). Explaining these basics would be tedious for people familiar with modelling, but would be necessary for a beginner. So if you don't yet know the difference between insert edge loop and split poly, this isn't the tutorial for you. (Note: In 2012 they've done some messing around with the split poly tool. I thought they'd changed it to “interactive split tool”, but it turns out they've kept the original functionality and added more in the new interactive split tool – either tool will work fine for custom splitting).

Having said that, for an intermediate user or someone who is comfortable at hard-surface modelling and wants to give organics a try, this is a great tutorial for that. The shapes are very roughly blocked out to start, and Jay gives good advice and uses a variety of tools to work efficiently and smoothly. Again, this progresses at a rapid pace, and I think it would be nice to have the instructor stop every now and again, take stock of what we have so far, what features the existing edge loops will define, and how to expect them to evolve as the form takes shape.

The fingers seemed to take shape quickly and simply. The edge flow of the arm and hand is clear and informative. After showing how to shape the thumb, Jay leaves the viewer to finish shaping the other fingers. This makes sense, however, it does mean that you shouldn't expect a final product in the 10 hours it takes to view the tutorial. Even if you are able to model and keep up while the tutorial is playing (which is it's own challenge as I mentioned), some "homework" is required.

I should add a note here about selecting modelling tools. Jay has a custom shelf that he uses. If you aren't familiar with where the commonly used tools are, a) maybe start with a more introductory tutorial, b) check the mesh and edit mesh menus, c) check the maya docs, d) use the find menu help tool, or e) ask the friendly folks over at SimplyMaya.com. I personally like to use marking menus to select common tools and commands. Again, in different versions of Maya, Autodesk likes to change the names of tools and menus, so either look in the docs, or head over to simplymaya and ask politely.

Jay gives plenty of good general advice on production quality models, common pitfalls, things people tend to forget, and has a good sense of humor. He doesn't gloss over errors, instead works through the troubleshooting and provides the solution, albeit sometimes without much explanation.

The lack of explanation is probably my main criticism of the tutorial. Since I work through at the same time as the video is playing, I really appreciate a running commentary on what is happening. This is present in large part, but often the audio is limited to “we'll grab this and move it around here.” Instead of "just move this there and give that a tweak" I would prefer the instructor to give things names (preferably using anotomical terms) or be a bit more specific about the verbal instructions (e.g. we'll pull the bridge of the nose a bit further out, or we'll push back the corners of the mouth). The head especially would benefit from that, because it was hard to anticipate which edge loops would be pulled out from the face and which would be pushed in to provide the desired contours. Even looking at the video, it's often difficult to see exactly what is being selected, so something like “grab the third innermost edge loop of the mouth” would go a long way in my opinion. To be fair, the commentary is very decent in places, but ideally, clear and anatomically based verbal guidelines throughout each chapter would be excellent.

The shaping sections get a bit tedious, being mostly vertex pushing, as the author acknowledges. Of course you can fast forward some bits and try to do the shaping on your own, however, I wouldn't recommend that for myself at least, because I would struggle trying to deduce the occasional topology adjustment and re-routing of edge loops that does happen. In fact, it can be tricky to work out exactly how Jay is modifying the topology, since my piece looked slightly different based on how I tweaked the vertices, and sometimes it's necessary to stop and puzzle out independently how to get the same topology.

Jay sometimes uses a custom script called spin-faces. You can find this on creativecrash.com, or do it manually which shouldn't be hard. However, in Maya 2012 there is now “spin edge forward” and “spin edge backward” under the edit mesh menu which does the same thing (just select the edge to rotate instead of the faces as Jay does).

After the alien was complete, it was fun to create some accessories, including clothes, jewellery, and a surfboard. Some different modelling techniques are introduced, including creative use of some non-linear deformers. Unfortunately the surfboard image planes don't seem to be included in the supplied files, but since the object is pretty simple, I didn't struggle with not having the reference (yes, it was part of the tutorial to put fins on top of the sufboard too; it is an alien after all).

The UV mapping for me was a highlight of the tutorial. UVing gets a bad rap, but under Jay's direction, it's not as tedious as you'd expect. Jay goes over helpful troubleshooting tips and solutions and workflow improvements. Like modelling the fingers, Jay leaves it to the viewer to UV the legs and feet since it's the same process as arms and legs.

There seems to be a bug near the end of part 15 where the audio continues but the video quits. I've contacted an admin at Simply Maya, and if it's not a problem on my computer's end, I'm sure it will get sorted out in no time. I've always had great success with the people over at Simply Maya.

Though there were times while following the tutorial that were frustrating or tedious and ultimately I wasn't that happy with how my alien's face turned out (it's my fault that it's kinda noobish looking), often I was reminded how fun it is to model in Maya, and I'm rather pleased with the final product as a whole. I'd recommend this tutorial to any intermediate modeller as excellent project-based training for organic modelling.

Thanks to Jay and Simply Maya!

P.P.S. (Personal Plug Script) If you're visiting from Simply Maya, welcome to my blog! I hope you stick around and check out some of my personal and biomedical projects.

SimplyMaya Rain & Snow Dynamics

Once again I've had the privilege of reviewing Simply Maya tutorials. This time there are two short tutorials centered around creating some precipitation effects, namely rain and snow. Each of these is quite short, but at the end of each you've got a pretty nice dynamics effect. This tutorial was created with Maya 2011, but I had no problems following along with 2009.

In the rain tutorial, like the previous tutorial I reviewed, the instructor moves quickly, so the effect takes shape quickly. If you're new to Maya, the speed of the tutorial is such that you'll get confused and will have to play it through several times, but if you're familiar moving around Maya and you want to get introduced to dynamics, this is a fun little adventure. It explores surprisingly many different aspects and features of the dynamics module including the collision events editor (new to me, I think) and per particle attributes such as lifespan and color. There's some nice tips that get mentioned as well as an introduction to the expression editor which I think is essential for a good understanding and use of dynamics. Adding believability with forces is well done in this tutorial, although the time isn't taken to really explain how the fields and their attributes work with the particles (air is an ambiguous field to start out with, and I'm still a bit confused as to what it really does). Another minor complaint I might have that prevents it from being a really polished tutorial is that the instructor doesn't really mention resetting tools and preparing the scene when users may have changed options and settings previously. For example I believe the timeline should be set to "Play every frame" when testing dynamics, but I'm not 100% sure if that's critical. The rendering, specifically using the hardware renderer, doesn't get adequately described in my opinion, which is why you'll probably want to go through both tutorials.

The snow tutorial starts out in much the same way as the rain tutorial, and one might think it would redundant to go through both. It's true there's some repeated information, however, there is plenty of new material here, and I'd encourage people to cover both to get a full introduction to both dynamics and weather effects. The intro to using sprites is great, and what many dynamics tutorials don't do, and what this one does, is actually get into how to create sprites with transparency in photoshop. I really liked that this was included. Also, the instructor goes into much more detail on rendering with the hardware and preparing the effect for compositing.

Overall, a couple of really nice introductions to dynamics, and a great refresher for those already somewhat familiar with this module of Maya.

SimplyMaya Production Workflow Review

SimplyMaya has recently released a new Effects tutorial based on a Production Workflow for creating a simple dynamic simulation of golden rings bouncing out of a falling wineglass. I was given the privilege of reviewing the tutorial and writing up my thoughts on it. This was a fun, relatively short (1.5hr) training kit that walked through importing simple geometry, creating and baking a rigid body simulation, adding shaders and lights (including FG, IBL, and GI) and rendering out two layers (a beauty pass and a depth pass). The depth pass was used in After Effects to add an animated depth of field filter, resulting in quite a beautiful 6 second animation that showcases some of the exciting things Maya is capable of without a tremendous amount of effort. The final animation and tutorial can be viewed and purchased, respectively, here.

The video training includes scene files and final renders, which is nice, since I didn't take the time to render out my final piece, so I could use the supplied frames for the DOF section. Though the version of Maya used in the tutorial was 2011, I used 2009 and had practically no problems tracking with the latest release. I did run into some issue importing the wineglass geometry, but got around it without too much trouble. Perhaps including an obj for the wineglass would save some version incompatibilities. (Update: It looks like an obj will be added to the assets folder on my suggestion.)

The instructor moves reasonably quickly, though the pacing is such that following along is generally feasible and the instruction remains clear and concise. It is made clear that the scope of the training isn't to slog through info on every attribute that is modified in this tutorial, which is fair enough. I might have liked to get a bit more information on some of the rigid body attributes, since I wasn't completely satisified with my sim. The rings felt quite "floaty" at times, and I didn't know how to fix that, though to be honest, I didn't spend much time on my own tweaking all the attributes. In the same vein, the lighting and rendering section was more of a recipe to be followed than a how-to, but since this wasn't a lighting tutorial, I wasn't expecting anything else. The tutorial did cover many good points on dynamics and lighting/rendering and I was happy to see a pleasing result appear on my screen with relatively little time and effort. The instructor's approach and British sense of humour also made the video training fun and interesting for the duration.

The real strength of the tutorial was to bring the viewer's attention to a myriad of components and features that can be exploited in a thousand ways to bring added appeal to whatever project one might be working on. For example, I was practically unaware of the attribute spreadsheet, which seems essential for modifying the attributes in a large number of objects. I was also unfamiliar with mental ray's approximation editor, so while the tutorial didn't explore either of these in great depth, they are editors I am aware of now and will study up on. Exploring After Effects a bit more was also fun, and introduced to me the power of depth of field and how it can be easily used to add punch and polish to any animation. I'm definitely going to adopt this DOF workflow in my animations.

So in summary, while there could be more depth and detailed explanation in this worflow tutorial and a beginner might scramble to keep up, it really is an excellent overview of many topics and was very enjoyable to work through. I'd recommend this tutorial for any intermediate user who wants to stretch out beyond the typical modelling monotony and explore some of Maya's other offerings.

Stuart