mental ray exercise

[ME3D]

all finished with the light excercise? It turned out pretty well.

Ah Mental ray now.....Have you tried the hdri yet?

Crit the spoon should be reflecting within the scoop so I imagine this need to be modeled with more detail in the scoop area. The orange looks good already so the cup and saucer are more of an issue right now. The Glass dish is looking good. I'd say a piece of glassware with a more complicated surface would be interesting for the caustics. Something like ....
http://www.me3d.tv/garry/Temp/glassware.jpg

[silvia]

Hey ME3D, where have you been? :)

I have posted a new version of the light exercise, thank you for asking!

That glass dish you posted, is it a photo or did you model it? If you modeled it, I think I am going to hide somewhere and cry...

For the reflections in the spoon, WELL SPOTTED! Do you know why? Because there is no ambience reflection... I tried to cover the scene with a dome with a HDR image on it, but it came out kind of screwy on the paper towel, so I removed it. But since you mentioned it, I think I am going to do a few more experiments with it.

Nice to hear from you though!

[ME3D]

I've been cranking to get a new demo out. I'd like to get back into a studio and am very hopeful it will be a bigger one this time. I'm getting tired of freelance.....maybe just lonely...lol

Go Check in on the rock city I'm working on I have the interior castle shot about ready ....which is similar to the shot your workin on. (v I have a link under this v)
I just took a picture of that for an example. I didnt model it....Way too much effort for me right now...
Oh the spoon is reflecting the black of the scene.....Gotcha

I have a good HDRI set up file I'll lend to you if you promise to not give it out. You can play with the settings then if you like or use the setup is fine. Just dont sell it. :)

good talkin with ya.

[silvia]

Oh, dude, I took a look at your work: way awsome!!! I love the room with the arches!! Good luck for getting into a studio, although if they don't take you with that kind of work, they are crazy! I'll cross my fingers for you, ok?

I managed to squeeze in the scene a HDRI I downloaded from the web and then modified in HDRShop. I think it looks ok and, well, obviously the spoon looks much better now!


http://members.lycos.co.uk/sysite/hpbimg/StillLife4.jpg

[ME3D]

Are you using the uffizi probe for the HDRI? the back of the cup above the liquid is noticably brighter and shows detail in reflection...Niiiiiiiiiiice!
Yeah the spoon does look much better...Strangly enough the handle is the same but all together it all fits and really adds to it now. So whats next? A table for this to set on or are you placing this into a photo?

I thought the arches might get your attention. After seeing your project, and another WIP in this section "Dragon Commander " I believe. I couldnt wait to jump to the next piece of my project and begin fleshing out the interior for the final shots. Plus that city is so big I needed a break.
Thanks I need some luck this next one ...got me starry eyed....lol
:drool: So much cool work to do so little time.

[rrobert]

Not very special I must say!! I don't want to be a pain in the ass but it just isn't beautifull JET ! The glass looks like something melted and then hardened. and the orange is to orange and the tissue underneeth is is to flat. Work on that, and you can have a lovely scene.

(Remember: Don't take this to hard, it is only Comment&Critic.)

Good luck: :thumbsup: :thumbsup: :thumbsup:

[silvia]

I don't know what kind of oranges you guys get in Holland, but let me assure you that in warmer places oranges are VERY orange... :)

[ME3D]

Took a quick digital pic of an orange from my kitchen. Its outside where its bright so youll have to consider it darker with inside lighting..http://www.me3d.tv/garry/Temp/orangeorange.jpg

[ME3D]

Notice the label where the orange is from. I just thought it was funny....not very but alittle.

I think the orange is fine bigger issue is the glass I agree.

So question is there any bump added to the glass or is refraction creating the bumpy look?

[silvia]

Hey, how do you always have the right photo at hand at the right moment??:beer:

The glass does have a bump map that I need to tweek a bit. I thought the definition of "something melted and put back together" was quite appropriate!!!:applause:

[DigitalCrystal]

Lookin' good. I never really considered much out side of MAX, but the more I see some of the stuff you can do with Vray, and Mental Ray.. brazil, and the like, I begin to wonder what rock I was born under :) Hopefully some day I'll maximize my max with some of those programs, but I just can't max the checkbook yet ;)

Lookin' good.:thumbsup:

[silvia]

You were probably born under the same rock I was born! That is my very first experiment with Mental Ray that includes more than a cube and a sphere... :)
I get quite impatient with Mental Ray because it takes so long to render, and usually the Maya renderer gives decent enough results. But for radiosity and caustics, I think Mental Ray does the work quite well!

[silvia]

Update with less bumpy glass.
I was having some cranky time with my web site, so I just overwrote the previous image.


http://members.lycos.co.uk/sysite/hpbimg/StillLife4.jpg

[d8ed]

a couple of things.. you've got bounce light illuminating the back of the orange yet your shadows are crisp and hard. same for the cup.. it shouldnt cast a hard shadow like that. the fact that you've got this scene floating in black space makes it very hard to believe. try using some area lights to soften up the shadows.

i cant tell what the saucer is made from.. it looks like a hammered polished chrome thing. is it metal or glass? either way it's not working too well.

also turn up the tesselation in the cup/saucer since you can see the polygons.

good luck. tough scene.

[silvia]

Thank you very much for the comments, they are very useful!
The shadows are so crisp because they are ray traced. I will have to change the parameters a little to soften them up.
The scene is not floating in space, it is set on a dark brown table. I got several comments about my work that things are too dark, while on my screen they seem to look fine. Probably our settings are different?
The cup and saucer are supposed to be glass. I took one of the glass shaders downloaded from Alias|Wavefront site, and changed some of the parameters to get the look I wanted but I realize it can be improved. Does anybody have some "recipies" for glass shaders?
And for the tassellation, you are perfectly right, it is rendered at the lowest anti-aliasing possible to keep the rendering time to acceptable levels, i.e. not having to tweak one parameter, then start the render, go to bed, and see the results the day after...
Once the whole thing is good, I'll do a final high quality render.
Well spotted, though!
As I said, this is a Mental Ray exercise, the 1st scene in which I tried to user Mental Ray, so no great expectations or anything. Comments from people who have more experience with it are GREATLY appreciated!

[d8ed]

honestly i know Mental Ray in XSI but have no idea what it's like to use it in Maya. for a first shot.. it's commendable ;)

it is however extremely hard to get photo realistic glass in any package and this being your first try with a new renderer, it's going to be that much harder.

the old and still useful way of doing glass used to be having two objects.. one with its polygons facing out and one with its polygons facing in sitting on top of each other. the outside facing polygon object would get the high refraction index.. 1.5 or 1.6 and 90% transparent and the inside polygon object would get 1.0 for refraction and about 95% transparent.

havent tried this with maya or mental ray so i'm not sure it'll work. i used to use it in lightwave a while back. worked well.

[silvia]

Wow, that's interesting, I never heard of having 2 objects as you described! I am definately going to try that one! What kind of material to you assign to the 2 objects: blinn or phong or what?

[d8ed]

phong should work just fine.

[silvia]

I went on and tried a few shaders and glass methods. Most looked like my shader so, I discarded them. Here are 2 variations I think look ok for glass. One is a bit more plastic looking than the other, less reflective. Which one do you think I should use?

http://home.attbi.com/~alan971/test.jpg

[d8ed]

i like the one on top. too much reflection is distracting.

[ME3D]

Looks like the Crit is doing well for you, so I'll chime in:

The saucers LOD may be something to address real quick. Part of why the glass hasnt looked just right seems like is at the outer edge of the saucer. Adding a Rib or more defined edge should clear it up. Ask me if thats not to clear.
Then the upper image is better mainly since you should see the liquid no matter what, but the lower image reflection totally knocks out the dark liquid.

Quite an improvement!
Taking it little by little....... the table under it will make a huge difference grounding it in the scene, and the edge of the tableclothe having falloff in the texture....Sorry to say so many things to address there.

[silvia]

Thank you very much for the help guys, you have no idea how much help you are giving me!
I also prefer the one with less reflection, also for the effect of the dark liquid and the foamy top that is more evident.
Now that I have a good enough glass texture, I can start working on other things, like softening the shadows, adding some more illumination, and yes better anti-aliasing.
Thank you very much for your patience with me guys, you are very very helpful!

[silvia]

I tried to soften the shadows without much result... will have to try more.
I rendered at a higher anti-aliasing quality, but I am sure that when i render at max it will look better.
I also turned on global illumination, but even though I crank up all the right attributes, it keeps having this spotty look.

http://alan971.home.attbi.com/StillLife6.jpg

[d8ed]

you're not using shadow maps right?

best way to soften shadows with an area light is to just make the area light bigger.

in XSI, to get rid of that blotchiness you need to turn up the accuracy.

now are you using final gathering? global illumination? caustics?

[silvia]

I am using a directional light rather than a area light, actually.
The shadows are raytraced. I don't know about XSI, but in Maya, you soften raytraced shadows by changing the "light angle" parameter.
For what concerns MR, I am using all of those things: caustics, final gather and global illumination. Changing parameters like accuracy, number of photons, etc didn't seem to make any difference.

[ME3D]

Hey Silvia,
Area light and directionals look cool and provide great results so I am in no way talking bad about them when I say I only use one light. I just did lots of tests to get the right speed and shadow out of spotlights....They render fast. Try a spotlight in here I have several setups for this but try this:
Cone angle: 80-60
Penumbra Angle: .800
Dropoff: 8

under shadows
Dmap filter size: 3

Some will say crank it higher, but thus far I diagree. Render times are less and if its not smooth enough you need other light in ther....Several spotlights are faster than one with the settings cranked...

Give er a shot I hope it helps. Your still welcome to the hdri setup I mentioned if it seems like an interest.

Later,
G

[ME3D]

I forgot to mention the caustics light needs raytracing right so just try these settings on the rest and for that one the ray trace settings should be tweeked in another preset.

[d8ed]

well there's your problem right there. a directional light shines rays that point in the same direction.. it's basically a far away light like the sun. if it's all you're using, the shadows will be pretty crisp. in real life however, you'll have a bunch of bounce light in the room and that'll soften your shadows for you. for that to work, you'd need an enclosed box around your scene to bounce the light back or you can switch to an area light. area lights are basically big rectangles and the bigger they are, the more light will wrap around the object making the shadow and soften it up.

[silvia]

Wow, that was really interesting!!! Where did you get those pictures?
My scene is enclosed inside a half dome which has a HDRI mapped to it. I need to try changing the light, see what happens. Thank you so much!

[d8ed]

i just made it real quick. personally i probably wouldnt use GI/FG but just caustics, an area light, and some spots. one main area that casts shadows/caustics and some fill spots (or areas again depending on how it looks) for each object depending on what they were.

it would be easier to sub in a plain grey table while you tweak your shadows and lights. worry about the wooden table top once everything else looks nice.

also might want to change the angle of the camera so that you dont see the black background. it would help with the realism a bit more.

hey check this link out.. found it last night.

http://www.blochi.com/gfx/hdri/

[silvia]

I have added a secondary light, instad of using global illumination (I like the result better and MR doesn't crash as often). I also changed the camera angle, and refined the table texture.

http://alan971.home.attbi.com/StillLife7.jpg

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