Mental Ray: worth learning?

[Nizar]

Always intimidated by mental ray: too many slider and parameters, apparently too slow compared to others modern render engines, but I like very much the render output and many time the Mental Ray masters leave me in awe with their outstanding works.

Actually I use modo and cycles for my render, and they fit my needs, but I'd like too operating all inside softimage reducing import/export (also, don't like so much modo workflow).

To me, learn mental ray, appears like a big task, an enormous effort in term of time and will. Worth learning it or is better invest time (and money) in another rendering? I mean 3deligth, vray or arnold (rather will be public released), or, even, octane?

I doing characters, occasionally some archiviz job but I aim to animation and VFX in a (I hope near) future.

[Hirazi Blue]

Ah, Render Wars...
The main reason to learn Mental Ray now is basically that you will have learned
at least one thing you can still use once Autodesk force us to switch to Max or Maya.


But seriously, I think Mental Ray is extremely underrated and has been getting a lot of unnecessary flak from all the user communities. It’s the product everybody “loves to hate”. It can be a pain to learn and an even bigger pain to master, but as they say “no pain, no gain”. (Mastery in itself, however, is always a pain, regardless of the renderer...)
On the other hand, there is obviously a lot to be said to concentrate your efforts on the renderer you feel most at home with as mastery of it/one (sort of) equals high-quality output and high-quality output matters more than being able to work with a wide array of render softwares. In the end only the "fanboys" ask what renderer you made your image with...
;)

[Letterbox]

Export from xsi the whole scene as fbx, and use cycles. Cycles is great because you can dynamically see what effects lights / shadeers etc have very quickly. Very nice.

Mental ray actually is not that hard, so invest in yourself, take a look at i3d's mental ray series.

Vray is and has shown it self to be very good at arch viz, BUT if you think mental ray has lots of parameters so does vray. But Vray's documentation is better. And for 20e there is very indepth pdf about vray.

3delight you can get free, (well 2 core) but you'll see that its simply (sort of) uses and existing render tree. To really maximize its output, you'll maybe need to know a lot more of the innards of it.

And that's the deal. What effort you put in, is what kind of renders you get out. What people never say in all of this, is to a large degree that what ever one you put the effort into, it will makes the others easier to master to. You just got to start somewhere.


But Nizar
---------
You've got modo and its good renderer, you've got cycles, you've got xsi, you've got mental ray, you've got 3delight. But you don't like the workflows? Stop thinking about it, pick one and stick with it, just suck it up, so sit down, strap in, get learning, and get it done. Otherwise my friend we'll be having this same conversation in a year from now.

[Nizar]

No Hirazi, don't want a render war. After pressed the "submit" button I realized this topic can degenerate into something not so useful...

Thanks for your advices.

LetterBox, I struggled with mental ray many time, but turn back to it because I like work with softimage and, as I said, import/export is not a so smooth operation. Modo, i.e., has a worse FBX importer, don't work well at all. Blender can communicate only with obj.
But struggle or not, mental ray seems overwhelming...
In modo can import my geometry and apply my displacement map, adjusting only two parameters into texture propitiates (low and high value). For more fine setting (in rare cases need to touch it) I can open material property and cage displacement distance, or, more fine (and even more rare) going into Render setting and cage displacement ratio or rate.

In mental ray I need to set a property value into Scalar Change Range (at least, need only to edit the two parameters New Range start and new range end, is more simple when you know the import value from zbrush), but not only I need to cage, with fine setting, the Geometry Approximation values (Polygon mesh subtab (angle and sunbdivision (ogl and render level) and Displacement (where can select Fine, parametric and Lengh/distance/angle), in "Fine" I have five slider to setting and one of the most important, lenght, can arrive to absurd value of 0.002...).

Also Global Illumination... in modo is a breeze, active it, select number of rays, adjust sample and antialiasing value (more fine setting=more quality=higher render time) and press render button (or F9). No photon/importon and whatelse (yes, I know Final Gathering is the best choice in mental ray)

Someone said mental ray is faster enough, would like understood how fast is and why (and I'm curios if the mental ray users, happy about mental ray, ever try different render engines)

[Rez007]

Hi Nizar,

I personally have not used any other render engine besides Mental Ray, so I really can't speak for the other engines. I really like Mental Ray and it is extremely powerful as well. In my opinion, it doesn't hurt to learn it to at least to some extent where you know your way around it. Everyone has their own opinion on what renderer to use, but I personally don't see a value in spending extra money/time when you have a powerful renderer already. Albeit, there are some things in Mental Ray that could be integrated better within Softimage. To me, I would rather save the extra cash than worry about if I save an extra second or two when it comes to a render - again that is for my personal needs, and I assume everyone has their own intentions on what they need.

To get you started (if interested) Unified Sampling is very nice and faster in the long run than Adaptive Sampling.

http://elementalray.wordpress.com/categ ... -sampling/ (you can scroll down for more info)
http://elementalray.wordpress.com/2011/ ... -sampling/ (I suggest to read the comment section as well)

There is a lot of valuable information on this website above dealing with Mental Ray that you might find useful. I personally like Unified Sampling, because depending on your purpose, you can play with the main sampling controls to greatly increase the speed/quality of a render than you can with Adaptive Sampling.

[bergj]

I think 3delight is a great renderer once you learn to read and write rsl so you can make an ubershader. Then, you can keep going and make a custom display driver and implement "relighting" so you can only rerender parts that have changed instead of the whole image without having to go out to an external compositor.

I remember using mental ray and it was such a nightmare when I was working on a character with sss and hair and dof. Once I learned rsl and began interpolating sss over a pointcloud and using deep shadow maps for hair and also using my custom relighting method I'm getting unbelievable results in small fractions of the time. Also, Im not really convinced that 3delight is required as you could use open-source pixie and use a python exporter to communicate with it.

[Nizar]

But Nizar
---------
You've got modo and its good renderer, you've got cycles, you've got xsi, you've got mental ray, you've got 3delight. But you don't like the workflows? Stop thinking about it, pick one and stick with it, just suck it up, so sit down, strap in, get learning, and get it done. Otherwise my friend we'll be having this same conversation in a year from now.

forgot to quote this. Obviously totally agree


Thanks Rez007, I will read this info about unified sampling.
Agree with you, is better know what just have purchased.

Bergj, thanks for reply. I don't know so much about 3delight and renderman world, so your argumentation sound to me a bit too technical.
About 3delight, there is no tutorial or documentation about, so look very complex to learn.

sorry, but this point is pretty obscure for me:

Also, Im not really convinced that 3delight is required as you could use open-source pixie and use a python exporter to communicate with it.

[ActionArt]

Then, you can keep going and make a custom display driver and implement "relighting" so you can only rerender parts that have changed instead of the whole image without having to go out to an external compositor...using my custom relighting method I'm getting unbelievable results in small fractions of the time.

This might be something worth packaging and selling.

Sounds very interesting.

[Nizar]

I reading the link suggested by Reez007, but why is all maya oriented? Is not softimage the best mental ray integration?
Obviously is mental and what work with maya work with softimage.

[Kerro Perro]

I learnt MR from just two tutorials: http://www.cmivfx.com/tutorials/view/31 ... ender+Tree and http://www.cmivfx.com/tutorials/view/32 ... and+Passes these are pricey but very good and "totally softimage" ;)

Buuut in my nooby opinion if you want to use final gather or global illumination in anything more complicated than simple camera animation forget about it, yes it can be done without flicker but the workaround are so cumbersome you'll get very frustrated. Well i did anyway ;)

Edit: oh and just to answer your other question yes i do use and am happy about it but personally when i use it i go without gi/fg and just do the old fashioned tricks of faking lighting. The reason i like it is maybe the reason you don't: i like all the nodes and options, pretty much any kind of effect or style i can think of is possible with enough fiddling and experimenting. And i don't use displacement ;)

[Falam]

I learnt MR from just two tutorials: http://www.cmivfx.com/tutorials/view/31 ... ender+Tree and http://www.cmivfx.com/tutorials/view/32 ... and+Passes these are pricey but very good and "totally softimage" ;)

Buuut in my nooby opinion if you want to use final gather or global illumination in anything more complicated than simple camera animation forget about it, yes it can be done without flicker but the workaround are so cumbersome you'll get very frustrated. Well i did anyway ;)

I read the entire Mental Ray Book for Artists, I believe it weights in at over 700 pages Then you have to go over parts, and over parts, it's a process, 3D is basically a complicated, surgical operation. You can't learn 80% of it at least properly in a few months, maybe not even a year.

[Rez007]

I reading the link suggested by Reez007, but why is all maya oriented? Is not softimage the best mental ray integration?

Hi Nizar,

It all depends on the main DCC tool that the person used making the presentations, Maya is pretty popular in big shops so that is probably why, but the basics apply to everything Metal Ray. If you check out the rest of the website too, there are more sections about Mental Ray and Unified Sampling.

http://elementalray.wordpress.com/categ ... ng/page/2/

Here is an older post, but if you look through it, it will give you a better explanation of how Unified Sampling works. I really like it, because it samples where you need it and it doesn't waste time sampling areas of your render where it doesn't need it.

I am not in front of Softimage right now, so I might be explaining the below comments somewhat wrong - anyone can feel free to step in and correct me...

The basics are this:
1.) Change your sampling method in the Render Manager to Unified Sampling (should be a check box for this on the main Mental Ray panel) otherwise it will be using Adaptive Sampling - the old method.

2.) This will enable new sampling controls (referenced in the links that I provided) you can play around with these controls to see what works best for you. Depending on your scene and your purposes you can get away with some really low numbers - just up the quality/samples from there to get the desired final render output that you are looking for.

3.) This is really important - On your materials that you are using change all of the sampling values to "1" - Example: If you are using the Architectural Shader with a Reflective value to it, where it says samples under the glossiness value (the default is usually set to 8 I think) change this to "1" What this does, is it tells the material to shoot one ray of sampling for that material. However, the main controls in the Render Manager - the min/max sampling portion on the main render panel - will dictate the actual sampling that will take place for that material. Now, if you are making a material that has a very low glossy level, say a glazed stone material for instance, then you might want to put the sampling of this material from "1" to "2" and so forth. This will alllow you to adjust certain materials independantly rather than having to jack up the sampling settings for the whole entire Render. If you don't change the sampling of the material to a very low number as "1" you are essentially telling Mental Ray to take this material sampling number and multiplying it to the Main Sampling min/max number when it renders...this can lead to wasted and unwanted sampling in areas that don't need it.

4.) Lights - if you are using Areas lights, these have Sampling as well. Do the same for the lights in the Area Shadow Panel as you would for the materials. Set their Sampling to "1" for the samples and test the outcome. Usually though, you will have to increase the samples of an Area light to more than "1" for a decent output - maybe "2" is a good value to use.

This is kind of the jist of working with Unified Sampling. If you work back and forth with the main Sampling window of the main Render Panel in conjunction with certain materials and lights, you can optimize your outcome. It seems like a lot to do, which it can be especially if you have 50+ materials all setup for Adaptive Sampling and you want to go back and change them. I suggested to Softimage Development that maybe they should make an Override for materials and one for lights on the main Render Panel, this way you can Turn the Override on and off so you dont have to go into each material to change the sampling.

I hope this helps and that I explained it correctly. If you start using Unified Sampling in Mental Ray, I think it is a really good idea that you get familiar with it if you plan to use Mental Ray more. As I think from what I have been reading, that future releases of Mental Ray should be setting up with this Sampling method in mind - it is just much more efficient.

Thanks.

[Rez007]

I learnt MR from just two tutorials: http://www.cmivfx.com/tutorials/view/31 ... ender+Tree and http://www.cmivfx.com/tutorials/view/32 ... and+Passes these are pricey but very good and "totally softimage" ;)

Buuut in my nooby opinion if you want to use final gather or global illumination in anything more complicated than simple camera animation forget about it, yes it can be done without flicker but the workaround are so cumbersome you'll get very frustrated. Well i did anyway ;)

Edit: oh and just to answer your other question yes i do use and am happy about it but personally when i use it i go without gi/fg and just do the old fashioned tricks of faking lighting. The reason i like it is maybe the reason you don't: i like all the nodes and options, pretty much any kind of effect or style i can think of is possible with enough fiddling and experimenting. And i don't use displacement ;)

Hi Kerro,

I must have gotten lucky, but I just finished up an animation using FG and Unified Sampling, and it came out flicker-free. I didn't use any pre-cache/bake method either of the FG map first and then render after. It was all in one go. The only thing I did do, which might have worked for me, was for the FG map, I used a blurred environment image which the sampling derived from...I think the less details that are in the map that FG uses to calculate, yields better results for non-flickering.

[Kerro Perro]

I learnt MR from just two tutorials: http://www.cmivfx.com/tutorials/view/31 ... ender+Tree and http://www.cmivfx.com/tutorials/view/32 ... and+Passes these are pricey but very good and "totally softimage" ;)

Buuut in my nooby opinion if you want to use final gather or global illumination in anything more complicated than simple camera animation forget about it, yes it can be done without flicker but the workaround are so cumbersome you'll get very frustrated. Well i did anyway ;)

I read the entire Mental Ray Book for Artists, I believe it weights in at over 700 pages Then you have to go over parts, and over parts, it's a process, 3D is basically a complicated, surgical operation. You can't learn 80% of it at least properly in a few months, maybe not even a year.

I didn't say i learnt all of 3d from it did i? I just said i learned MR from by wich i meant i learned how to use it in softimage. As Nizar already has experience of other renderers that's all he needs - not to learn the fundementals of 3d graphics!

[Kerro Perro]

I learnt MR from just two tutorials: http://www.cmivfx.com/tutorials/view/31 ... ender+Tree and http://www.cmivfx.com/tutorials/view/32 ... and+Passes these are pricey but very good and "totally softimage" ;)

Buuut in my nooby opinion if you want to use final gather or global illumination in anything more complicated than simple camera animation forget about it, yes it can be done without flicker but the workaround are so cumbersome you'll get very frustrated. Well i did anyway ;)

Edit: oh and just to answer your other question yes i do use and am happy about it but personally when i use it i go without gi/fg and just do the old fashioned tricks of faking lighting. The reason i like it is maybe the reason you don't: i like all the nodes and options, pretty much any kind of effect or style i can think of is possible with enough fiddling and experimenting. And i don't use displacement ;)

Hi Kerro,

I must have gotten lucky, but I just finished up an animation using FG and Unified Sampling, and it came out flicker-free. I didn't use any pre-cache/bake method either of the FG map first and then render after. It was all in one go. The only thing I did do, which might have worked for me, was for the FG map, I used a blurred environment image which the sampling derived from...I think the less details that are in the map that FG uses to calculate, yields better results for non-flickering.

Hmm that is interesting because the flicker problem is pretty well known so if you have a simple method that works a think a lot of people would be very interested.

[Rez007]

Hmm that is interesting because the flicker problem is pretty well known so if you have a simple method that works a think a lot of people would be very interested

Yes it is a well-known issue, but there are others who have generated flicker-free animation using the same technique that I have. Maybe a lot of people keep just thinking if they throw in a HD Reflection map and use that to derive an FG output that all will work - that might be one of the main problems. All I did was this 1.) Unified Sampling (I don't know for sure if this has a great effect difference from Adaptive Sampling, I just tend to use this method and no more AS) and 2.) Use a blurred image to calculate FG. and 3.) I believe I have the FG algorithm set to "Multiframe" - I am not in front of Softimage right now, but I thnk that is what it was set to. You can take it for what it is worth, but I am just saying that this is how I get flicker-free animation...and then of course which is mentioned in the links provided, I guess you can brute force FG if you have the time...