Hi Ludvik, and thank you for this making-of, absolute wonderful. Looking through your sample scene files, I see that your colour in diffuse slot, for the white walls, are set with value 1, 100% white. As you say, never go over .75 for white, is this an error or intended? Again wonderful work:)
Anyone finding these reflectivity values much too high for mental ray w/ in maya? (i'm building some leaf textures) close ups of the leaves have lots of sky reflection off the leaf; especially at glancing angles. The value of 0.35 suggested here looks better to me at 0.035? An I missing something...?
Hello there. Great images, tnks for sharing :)
Only use it in non-metal materials, for metals use the 0/90 reflectivity control and the brdf curve... that way you can aproximate more the complex refraction index of a metal, since non-metals have a simple IOR.
Use refractiveindex.info to calculate the IOR and K of each wavelength and the aproximate it with the "0/90 brdf curve control".
Anyways, in the end of the day will not matter that much, but that's more correct for sure.
OK. I understand using the IOR to drive the BRDF curve, but if you take glass as an example, this will become practically 100% reflective at extreme glancing angles as will many other materials (to a degree) by limiting the upper level of your reflection to 75 percent, will give less physically accurate results? should you let the A&D materials own energy conservation balance the upper limit of your reflection and keep your reflection at values closer to 100 percent?
Thanks for disscussing this.
PS. thank you for the tutorials. The images are stunning.
Exactly, this what I learn form the fxphd class with Master Zap as well. Perhaps 0.75 is the trick ;-) Have you ever compared vray and mental ray and the IOR values? Even with the same value, let's say 1.6 the fresnel looks different between the two render engines. In mental ray one can use 25 or higher for metal reflections, this is not working in vray I would say.
I don't understand mentalray's IOR units - metals going up into the 30's and 40's seems far to high. Chromium is around 3.6. This is the value I get in Maxwell as well. However in mentalray I have to use such high numbers?
I know what you mean. I thought they are all based on the same formula of Fresnel, hm. In Vray a IOR of 3 is almost as reflective as 25 or so in mr. indeed strange. I would also like to know the explanation.. @Wizlon
@FlorianDubiel I understand how the A&D material works and how to use it. but the units seem arbitrary don't you think? especially when using an IOR for metals at 50! as opposed to real world values like 3.6. Maxwell will use 1.5 for glass and 3.2 for chrome, these values are more understandable and realistic.
In mentalray we use a value of 1.5 for glass and then 50 for chrome? why? I think I need to ask Zap.
On point 2 of your A&D tips you say
'You should never use reflectivity larger than 0.75 unless there are some specific cases for it, such as mirror material, where you can use 0.9 for example.'
I assume you mean for BRDF 0 degree reflection? as many surfaces will become almost 100 percent reflective at extreme glancing angles (BRDF 90 degree).
@Wizlon No, as i said, you should avoid manually changing 0 and 90 degree reflectivity, and set it to BRDF by IOR, so reflectivity falloff gets derived from IOR value of your material. By reflectivity not larger than 0,75 i was referring to reflectivity parameter in reflection parameters of A&D material.
@Wizlon Glass is one of the exceptions, where you can use higher value. You can download my sample scene and look at how glass is set up. Reflectivity is all the way at 1.
One of the most detailed break-downs ever posted ! Makes me even want to try MR again :- )Diky a tesim sa na Lightning
Hi, this is an awesome breakdown of your work. Valuable in many ways.
I enjoyed mostly your list of tips for the use of A&D materials, and I was wondering if the same general tips are to be applied (where possible) for vray material settings. What would you say about it?
@miki3d Not going over 0,75 white (in vray i would say about 220 white) and under 0,04 (in Vray 8), because Vray uses 0-255 range might give you slightly more realistic color range.
Using mostly glossiness maps instead reflectivity maps should apply too.
And for BRDF by IOR in Vray material, you just check on "Fresnel reflections" checkbox, or something like that.
Rest are pretty much tips to avoid sampling problems, but Vray has a lot better DMC AA sampler, so it does not apply there :)
awesome work dude !!! great summery of A&D material settings !! Thousand thanks for sharing this information :) @ paulpriv: you are not alone with Maya :) I am working in the automotive visualization industry and we are using Maya, mental ray + Vray. For private architectural visualizations projects I am using Maya too. I am very jealous about tools like MulitScatter for 3ds Max. That is really a pain in the a... in Maya.
@FlorianDubiel You should have PaintFX, which Alessandro Prodan used in Maya when creating his Farnsworth house using MR ;-)
I have poured over those images by Proden many times over the past few years, it remains some of the finest arch work I've ever seen in MR. lots of the text from that thread of comments is in my rendering reference sheets. I use PaintFX for grass but its such a nightmare... I agree w/ Florian Multiscatter looks so much easier to use ( I just want to scatter about some qlty trees that i have in my library it shouldn't be so hard) Ronan how about getting Prodan to do a paintFX tutorial for us!!!
I must be the only person on earth using maya and mental ray for arch viz... Nevertheless this is a fantastic tutorial that will surely become part of my reference sheets whenever I'm working on renders. I have enjoyed the simplicity of the A&D materials in the past but have not yet achieved the level of realism that you've show here... remarkable. Really appreciate your insight into the calculations that drive the renders and the general rules to follow… it goes to 11.
Wow I was impressed by your images first time I saw them, but it's only when looking at this article that I really realize how awesome your shaders are ! The wood ones in particular leave speechless !
Thanks for your articles !
great!! I've to work it out...really good job, and as the last time: i can't wait for the next part of your tutorialgreets from berlin, thomas
First of all, congratulations for the excellent work.
In my opinion you have created some of the finest archviz images of that style. Specially your shaders have caught my attention.
I would like to see more archviz work of that level of quality done with Mental Ray.
Can you share your opinion about using iray and how it helps to speed up the production with us? Also I would like to know about the rendertimes you got with your final exterior and interior renderings/size in pixels...Keep up the excellent work!
iRay has a lot of limitations. It does not speed up anything. It is unbiased renderer like any other (Maxwell, Fryrender, Indigo, etc...) but with benefit of possible (although not necessary) GPU acceleration, very easy setup, and usage of same A&D shader as MR uses. It does not at the moment support for example instancing, motion blur, ambient occlussion, many procedural maps, camera clipping, disabling of visual components (reflections, refractions, shadows). But still might be quite efficient and provide you with great results, if you have a f*****g gold mine to sell and buy a bunch of tesla GPUs ;-)
Final output frames were 1920x1080, and average rendertime was 8 hours on a single shot. I could push it down to 4, without minimal quality difference, but since it was a personal project, i did not care about a deadline, and went only for high quality without severe optimization.